diff --git a/src/phase_z2_pipeline.py b/src/phase_z2_pipeline.py
index ec4b586..ab3c2a1 100644
--- a/src/phase_z2_pipeline.py
+++ b/src/phase_z2_pipeline.py
@@ -128,6 +128,11 @@ GRID_GAP = 14                  # zone 간격 (사용자 직설 2026-05-07)
 # token-based font (var(--font-body) 11px 등) 기준 최소 가독 높이.
 DEFAULT_ZONE_MIN_HEIGHT_PX = 100
 
+# Step 14 image_aspect_mismatch tolerance — |natural_ratio - rendered_ratio| > TOL ⇒ fail.
+# Local anchor : IMP-15 실행-1 (Gitea issue #45) — image axis acceptance criteria.
+# Spec doc row (PHASE-Z-FIT-CLASSIFIER-ROUTER-SPEC) update deferred to IMP-15 실행-4.
+IMAGE_ASPECT_DELTA_TOL = 0.05
+
 # content_weight 계산 가중치
 CONTENT_WEIGHT_COEFFS = {
     "text_per_chars": 800,    # text_len / 800 = score
@@ -2208,7 +2213,53 @@ def run_overflow_check(html_path: Path) -> dict:
                 });
             });
 
-            return { slide: slideM, slide_body: bodyM, zones, frame_slot_metrics, zone_geometries_px };
+            // IMP-15 실행-1 (issue #45) — image_events[] for image_aspect_mismatch detection.
+            // 하나의 entry per <img> under .slide. natural vs rendered aspect 비교.
+            // zone_position : closest('.zone') data-zone-position. 없으면 literal "unknown".
+            const image_events = [];
+            slide.querySelectorAll('img').forEach((img) => {
+                const parentZone = img.closest('.zone');
+                const zonePos = parentZone
+                    ? (parentZone.getAttribute('data-zone-position') || 'unknown')
+                    : 'unknown';
+                const zoneTid = parentZone
+                    ? (parentZone.getAttribute('data-template-id') || '?')
+                    : '?';
+                const imgRect = img.getBoundingClientRect();
+                const rendered_w = imgRect.width;
+                const rendered_h = imgRect.height;
+                const natural_w = img.naturalWidth;
+                const natural_h = img.naturalHeight;
+                const natural_ratio = (natural_w > 0 && natural_h > 0)
+                    ? (natural_w / natural_h)
+                    : null;
+                const rendered_ratio = (rendered_w > 0 && rendered_h > 0)
+                    ? (rendered_w / rendered_h)
+                    : null;
+                const delta = (natural_ratio !== null && rendered_ratio !== null)
+                    ? (rendered_ratio - natural_ratio)
+                    : null;
+                image_events.push({
+                    src: img.getAttribute('src') || '',
+                    zone_position: zonePos,
+                    zone_template_id: zoneTid,
+                    natural_w: natural_w,
+                    natural_h: natural_h,
+                    rendered_w: Math.round(rendered_w),
+                    rendered_h: Math.round(rendered_h),
+                    natural_ratio: natural_ratio,
+                    rendered_ratio: rendered_ratio,
+                    delta: delta,
+                    bbox: {
+                        x: Math.round(imgRect.left - slideRect.left),
+                        y: Math.round(imgRect.top - slideRect.top),
+                        w: Math.round(rendered_w),
+                        h: Math.round(rendered_h),
+                    },
+                });
+            });
+
+            return { slide: slideM, slide_body: bodyM, zones, frame_slot_metrics, zone_geometries_px, image_events };
         """)
 
         screenshot_path = html_path.parent / "preview.png"
@@ -2248,6 +2299,25 @@ def run_overflow_check(html_path: Path) -> dict:
                 f"(content {c['scrollHeight']} vs container {c['clientHeight']})"
             )
 
+    # IMP-15 실행-1 (issue #45) — image_aspect_mismatch aggregation.
+    # |natural_ratio - rendered_ratio| > IMAGE_ASPECT_DELTA_TOL ⇒ fail_reason append.
+    # Entries with null ratio (image not loaded / natural dims = 0) are skipped (no false positive).
+    for ev in result.get("image_events", []):
+        delta = ev.get("delta")
+        if delta is None:
+            continue
+        if abs(delta) > IMAGE_ASPECT_DELTA_TOL:
+            n_ratio = ev.get("natural_ratio")
+            r_ratio = ev.get("rendered_ratio")
+            src = ev.get("src", "")
+            pos = ev.get("zone_position", "unknown")
+            tid = ev.get("zone_template_id", "?")
+            fail_reasons.append(
+                f"image aspect mismatch in zone--{pos}: "
+                f"natural={n_ratio:.3f} rendered={r_ratio:.3f} delta={delta:+.3f} "
+                f"(template={tid}, tol={IMAGE_ASPECT_DELTA_TOL}, src={src})"
+            )
+
     result["passed"] = len(fail_reasons) == 0
     result["fail_reasons"] = fail_reasons
     return result
@@ -4355,7 +4425,8 @@ def run_phase_z2_mvp1(
         note=(
             "Selenium 실측 — clientHeight / scrollHeight / excess_y / frame_slot_metrics. "
             "Step 8 의 계획값과 비교 시 어느 cell 이 overflow 했는지 박힘. "
-            "image / table 검사 부재 — Step 14 ⚠ partial."
+            "image_aspect_mismatch 검사 추가 (IMP-15 실행-1, issue #45) — image_events[] + fail_reasons. "
+            "table 검사 부재 (실행-2 잔류) — Step 14 ⚠ partial (table only)."
         ),
     )
 
diff --git a/tests/phase_z2/test_phase_z2_step14_image_check.py b/tests/phase_z2/test_phase_z2_step14_image_check.py
new file mode 100644
index 0000000..9377e67
--- /dev/null
+++ b/tests/phase_z2/test_phase_z2_step14_image_check.py
@@ -0,0 +1,196 @@
+"""IMP-15 실행-1 (Gitea issue #45) — Step 14 image_aspect_mismatch detection.
+
+Tests Selenium-driven `<img>` aspect measurement added to ``run_overflow_check``:
+
+* Fixture A — 200×100 image rendered at 200×100 → ``abs(delta) < tol``, no fail
+  reason, ``passed=True``.
+* Fixture B — 200×100 image forced to render 200×200 → ``abs(delta) > 0.30``,
+  fail reason includes ``image aspect mismatch in zone--primary:``,
+  ``passed=False``.
+* Fixture C — ``<img>`` with no ``.zone`` ancestor (attached directly under
+  ``.slide``) → event reports ``zone_position == "unknown"``.
+
+Chromedriver resolution mirrors the pipeline's order
+(``PROJECT_ROOT/chromedriver{,.exe}`` → PATH fallback). When no driver is
+resolvable the suite skips by default; under ``PHASE_Z_REQUIRE_SELENIUM=1`` the
+tests are marked ``xfail(strict=True)`` so CI cannot silently lose coverage.
+"""
+from __future__ import annotations
+
+import os
+import shutil
+from pathlib import Path
+
+import pytest
+
+from src.phase_z2_pipeline import (
+    IMAGE_ASPECT_DELTA_TOL,
+    PROJECT_ROOT,
+    run_overflow_check,
+)
+
+PIL_Image = pytest.importorskip("PIL.Image", reason="Pillow required for fixture PNGs")
+
+
+# ─── chromedriver skip / xfail guard ─────────────────────────────────
+
+def _selenium_manager_resolvable() -> bool:
+    """Probe ``webdriver.Chrome(options=...)`` — pipeline's third tier.
+
+    ``src/phase_z2_pipeline.py`` (run_overflow_check) tries
+    ``PROJECT_ROOT/chromedriver{,.exe}`` first, then falls back to
+    ``webdriver.Chrome(options=options)`` which delegates to Selenium Manager
+    for driver auto-resolution.  The test resolver must mirror that fallback
+    or PHASE_Z_REQUIRE_SELENIUM=1 produces spurious strict-XPASS failures on
+    machines where Selenium Manager can satisfy the pipeline at runtime.
+    """
+    try:
+        from selenium import webdriver
+        from selenium.webdriver.chrome.options import Options as _Opts
+    except Exception:
+        return False
+    opts = _Opts()
+    opts.add_argument("--headless=new")
+    opts.add_argument("--no-sandbox")
+    opts.add_argument("--disable-dev-shm-usage")
+    try:
+        drv = webdriver.Chrome(options=opts)
+    except Exception:
+        return False
+    try:
+        drv.quit()
+    except Exception:
+        pass
+    return True
+
+
+def _chromedriver_resolvable() -> bool:
+    """Mirror pipeline order: PROJECT_ROOT/chromedriver{,.exe} → PATH → Selenium Manager."""
+    for candidate in (PROJECT_ROOT / "chromedriver", PROJECT_ROOT / "chromedriver.exe"):
+        if candidate.is_file():
+            return True
+    if shutil.which("chromedriver") or shutil.which("chromedriver.exe"):
+        return True
+    return _selenium_manager_resolvable()
+
+
+_REQUIRE_SELENIUM = os.environ.get("PHASE_Z_REQUIRE_SELENIUM") == "1"
+_DRIVER_AVAILABLE = _chromedriver_resolvable()
+
+if not _DRIVER_AVAILABLE:
+    if _REQUIRE_SELENIUM:
+        pytestmark = pytest.mark.xfail(
+            strict=True,
+            reason="PHASE_Z_REQUIRE_SELENIUM=1 but chromedriver is unresolvable",
+        )
+    else:
+        pytestmark = pytest.mark.skip(
+            reason=(
+                "chromedriver unresolvable (PROJECT_ROOT/chromedriver{,.exe} + PATH + Selenium Manager); "
+                "set PHASE_Z_REQUIRE_SELENIUM=1 to make this a hard failure"
+            ),
+        )
+
+
+# ─── HTML / PNG fixture helpers ──────────────────────────────────────
+
+_SLIDE_CSS = """
+html, body { margin: 0; padding: 0; }
+.slide { width: 1280px; height: 720px; position: relative; box-sizing: border-box; }
+.zone { display: block; }
+"""
+
+
+def _write_png(path: Path, width: int, height: int, colour=(120, 160, 200)) -> Path:
+    img = PIL_Image.new("RGB", (width, height), colour)
+    img.save(path, format="PNG")
+    return path
+
+
+def _write_slide_html(tmp_path: Path, body_inner: str, name: str = "slide.html") -> Path:
+    html = (
+        "<!doctype html><html><head><meta charset='utf-8'>"
+        f"<style>{_SLIDE_CSS}</style></head><body>"
+        '<div class="slide" data-page="1">'
+        f"{body_inner}"
+        "</div></body></html>"
+    )
+    path = tmp_path / name
+    path.write_text(html, encoding="utf-8")
+    return path
+
+
+def _find_event(events, src_basename: str) -> dict:
+    for ev in events:
+        if Path(ev.get("src", "")).name == src_basename:
+            return ev
+    raise AssertionError(f"image_events missing entry for {src_basename}; got {events}")
+
+
+# ─── tests ───────────────────────────────────────────────────────────
+
+def test_image_no_distortion(tmp_path: Path) -> None:
+    """Fixture A — 200×100 image rendered at native 200×100. delta ≈ 0."""
+    png = _write_png(tmp_path / "ok.png", 200, 100)
+    body = (
+        '<div class="zone" data-zone-position="primary" data-template-id="t_ok">'
+        f'<img src="{png.name}" style="width:200px;height:100px;display:block">'
+        "</div>"
+    )
+    html_path = _write_slide_html(tmp_path, body, name="ok.html")
+    result = run_overflow_check(html_path)
+
+    assert "error" not in result, result
+    assert result.get("image_events"), "image_events must be populated"
+
+    ev = _find_event(result["image_events"], png.name)
+    assert ev["zone_position"] == "primary"
+    assert ev["natural_w"] == 200 and ev["natural_h"] == 100
+    assert ev["rendered_w"] == 200 and ev["rendered_h"] == 100
+    assert ev["delta"] is not None and abs(ev["delta"]) < IMAGE_ASPECT_DELTA_TOL
+
+    image_fails = [r for r in result.get("fail_reasons", []) if r.startswith("image aspect mismatch")]
+    assert image_fails == [], f"unexpected image fail_reasons: {image_fails}"
+    assert result["passed"] is True, result.get("fail_reasons")
+
+
+def test_image_forced_distortion(tmp_path: Path) -> None:
+    """Fixture B — 200×100 image forced to 200×200. delta > 0.30, fail emitted."""
+    png = _write_png(tmp_path / "bad.png", 200, 100, colour=(200, 80, 80))
+    body = (
+        '<div class="zone" data-zone-position="primary" data-template-id="t_bad">'
+        f'<img src="{png.name}" style="width:200px;height:200px;display:block">'
+        "</div>"
+    )
+    html_path = _write_slide_html(tmp_path, body, name="bad.html")
+    result = run_overflow_check(html_path)
+
+    assert "error" not in result, result
+    ev = _find_event(result["image_events"], png.name)
+    assert ev["natural_w"] == 200 and ev["natural_h"] == 100
+    assert ev["rendered_w"] == 200 and ev["rendered_h"] == 200
+    assert ev["delta"] is not None and abs(ev["delta"]) > 0.30
+
+    image_fails = [r for r in result.get("fail_reasons", []) if r.startswith("image aspect mismatch")]
+    assert len(image_fails) == 1, f"expected one image fail_reason, got: {image_fails}"
+    msg = image_fails[0]
+    assert msg.startswith("image aspect mismatch in zone--primary:"), msg
+    assert "natural=2.000" in msg and "rendered=1.000" in msg
+    assert f"src={png.name}" in msg or png.name in msg
+    assert result["passed"] is False
+
+
+def test_image_no_zone_ancestor(tmp_path: Path) -> None:
+    """Fixture C — <img> attached directly under .slide → zone_position == 'unknown'."""
+    png = _write_png(tmp_path / "loose.png", 200, 100, colour=(80, 200, 120))
+    body = f'<img src="{png.name}" style="width:200px;height:100px;display:block">'
+    html_path = _write_slide_html(tmp_path, body, name="loose.html")
+    result = run_overflow_check(html_path)
+
+    assert "error" not in result, result
+    ev = _find_event(result["image_events"], png.name)
+    assert ev["zone_position"] == "unknown"
+    assert ev["natural_w"] == 200 and ev["natural_h"] == 100
+    assert ev["delta"] is not None and abs(ev["delta"]) < IMAGE_ASPECT_DELTA_TOL
+    image_fails = [r for r in result.get("fail_reasons", []) if r.startswith("image aspect mismatch")]
+    assert image_fails == []