diff --git a/packages/client/src/pages/mfm-cheat-sheet.vue b/packages/client/src/pages/mfm-cheat-sheet.vue
index 1946d17ce4..a52cacdd43 100644
--- a/packages/client/src/pages/mfm-cheat-sheet.vue
+++ b/packages/client/src/pages/mfm-cheat-sheet.vue
@@ -137,6 +137,18 @@
 						</div>
 					</div>
 				</div>
+				<div class="section _block">
+					<div class="title">{{ i18n.ts._mfm.blockMath }}</div>
+					<div class="content">
+						<p>{{ i18n.ts._mfm.blockMathDescription }}</p>
+						<div class="preview">
+							<Mfm :text="preview_blockMath" />
+							<MkTextarea v-model="preview_blockMath"
+								><template #label>MFM</template></MkTextarea
+							>
+						</div>
+					</div>
+				</div>
 				<!-- deprecated
 		<div class="section _block">
 			<div class="title">{{ i18n.ts._mfm.search }}</div>
@@ -427,6 +439,7 @@ let preview_blockCode = $ref(
 	'```\n~ (#i, 100) {\n\t<: ? ((i % 15) = 0) "FizzBuzz"\n\t\t.? ((i % 3) = 0) "Fizz"\n\t\t.? ((i % 5) = 0) "Buzz"\n\t\t. i\n}\n```'
 );
 let preview_inlineMath = $ref("\\(x= \\frac{-b' \\pm \\sqrt{(b')^2-ac}}{a}\\)");
+let preview_blockMath = $ref("\\[x= \\frac{-b' \\pm \\sqrt{(b')^2-ac}}{a}\\]");
 let preview_quote = $ref(`> ${i18n.ts._mfm.dummy}`);
 let preview_search = $ref(`${i18n.ts._mfm.dummy} 検索`);
 let preview_jelly = $ref("$[jelly 🍮] $[jelly.speed=5s 🍮]");