diff --git a/components/index.html b/components/index.html
index 615c223..469a90f 100644
--- a/components/index.html
+++ b/components/index.html
@@ -21,17 +21,17 @@ <h1>KRDS Component Library</h1>
       <h2>Button</h2>
       <p class="src">.krds-btn · Figma Action/Button 36:67</p>
       <div class="row">
-        <button class="krds-btn krds-btn--primary">Primary</button>
-        <button class="krds-btn krds-btn--secondary">Secondary</button>
-        <button class="krds-btn krds-btn--tertiary">Tertiary</button>
-        <button class="krds-btn krds-btn--danger">Danger</button>
-        <button class="krds-btn krds-btn--primary" disabled>Disabled</button>
-        <button class="krds-btn krds-btn--primary krds-btn--loading">Loading</button>
+        <button type="button" class="krds-btn krds-btn--primary">Primary</button>
+        <button type="button" class="krds-btn krds-btn--secondary">Secondary</button>
+        <button type="button" class="krds-btn krds-btn--tertiary">Tertiary</button>
+        <button type="button" class="krds-btn krds-btn--danger">Danger</button>
+        <button type="button" class="krds-btn krds-btn--primary" disabled>Disabled</button>
+        <button type="button" class="krds-btn krds-btn--primary krds-btn--loading">Loading</button>
       </div>
       <div class="row mt-16">
-        <button class="krds-btn krds-btn--primary krds-btn--sm">Small</button>
-        <button class="krds-btn krds-btn--primary">Medium</button>
-        <button class="krds-btn krds-btn--primary krds-btn--lg">Large</button>
+        <button type="button" class="krds-btn krds-btn--primary krds-btn--sm">Small</button>
+        <button type="button" class="krds-btn krds-btn--primary">Medium</button>
+        <button type="button" class="krds-btn krds-btn--primary krds-btn--lg">Large</button>
       </div>
     </section>
 
@@ -92,8 +92,8 @@ <h2>Badge &amp; Tag</h2>
         <span class="krds-badge krds-badge--danger">Danger</span>
       </div>
       <div class="row mt-16">
-        <span class="krds-tag">필터 A <button class="krds-tag__remove" aria-label="필터 A 제거">×</button></span>
-        <span class="krds-tag">필터 B <button class="krds-tag__remove" aria-label="필터 B 제거">×</button></span>
+        <span class="krds-tag">필터 A <button type="button" class="krds-tag__remove" aria-label="필터 A 제거">×</button></span>
+        <span class="krds-tag">필터 B <button type="button" class="krds-tag__remove" aria-label="필터 B 제거">×</button></span>
       </div>
     </section>
 
@@ -102,9 +102,9 @@ <h2>Tabs</h2>
       <p class="src">.krds-tabs · Figma Layout/Tabs 59:11</p>
       <div class="krds-tabs">
         <div class="krds-tabs__list" role="tablist">
-          <button class="krds-tab" role="tab" aria-selected="true" aria-controls="tp1" id="t1">개요</button>
-          <button class="krds-tab" role="tab" aria-selected="false" aria-controls="tp2" id="t2">근거</button>
-          <button class="krds-tab" role="tab" aria-selected="false" aria-controls="tp3" id="t3">참고</button>
+          <button type="button" class="krds-tab" role="tab" aria-selected="true" aria-controls="tp1" id="t1">개요</button>
+          <button type="button" class="krds-tab" role="tab" aria-selected="false" aria-controls="tp2" id="t2">근거</button>
+          <button type="button" class="krds-tab" role="tab" aria-selected="false" aria-controls="tp3" id="t3">참고</button>
         </div>
         <div class="krds-tabpanel" role="tabpanel" id="tp1" aria-labelledby="t1">개요 패널 내용입니다.</div>
         <div class="krds-tabpanel" role="tabpanel" id="tp2" aria-labelledby="t2" hidden>근거 패널 내용입니다.</div>
@@ -155,7 +155,7 @@ <h2>Alert</h2>
     <section class="story" id="s-toast">
       <h2>Toast</h2>
       <p class="src">.krds-toast · Figma Feedback/Toast 56:46</p>
-      <div class="krds-toast">저장되었습니다. <button class="krds-toast__action">실행 취소</button></div>
+      <div class="krds-toast">저장되었습니다. <button type="button" class="krds-toast__action">실행 취소</button></div>
     </section>
   </main>
 </body>
diff --git a/tests/test_component_gallery_security.py b/tests/test_component_gallery_security.py
index 8eaf9e4..077db9d 100644
--- a/tests/test_component_gallery_security.py
+++ b/tests/test_component_gallery_security.py
@@ -82,3 +82,11 @@ def test_component_gallery_inputs_have_length_limits() -> None:
         if 'type="checkbox"' in inp or 'type="radio"' in inp:
             continue
         assert 'maxlength=' in inp, f"Input missing maxlength: {inp}"
+
+
+def test_component_gallery_buttons_have_explicit_type() -> None:
+    """Ensure all buttons explicitly define a type to prevent accidental form submissions."""
+    html = _gallery_html()
+    buttons = re.findall(r'<button[^>]*>', html)
+    for btn in buttons:
+        assert 'type=' in btn, f"Button missing explicit type: {btn}"