diff --git a/packages/backend/package.json b/packages/backend/package.json
index 3ace82166..bbc058bd1 100644
--- a/packages/backend/package.json
+++ b/packages/backend/package.json
@@ -60,6 +60,7 @@
 		"json5-loader": "4.0.1",
 		"jsonld": "6.0.0",
 		"jsrsasign": "10.5.25",
+		"katex": "^0.16.0",
 		"koa": "2.13.4",
 		"koa-bodyparser": "4.3.0",
 		"koa-favicon": "2.1.0",
diff --git a/packages/backend/src/mfm/to-html.ts b/packages/backend/src/mfm/to-html.ts
index 06acaeceb..35ca6b1e6 100644
--- a/packages/backend/src/mfm/to-html.ts
+++ b/packages/backend/src/mfm/to-html.ts
@@ -1,4 +1,5 @@
 import { JSDOM } from 'jsdom';
+import katex from 'katex';
 import * as mfm from 'mfm-js';
 import config from '@/config/index.js';
 import { UserProfiles } from '@/models/index.js';
@@ -6,6 +7,14 @@ import { extractMentions } from '@/misc/extract-mentions.js';
 import { intersperse } from '@/prelude/array.js';
 import { toPunyNullable } from '@/misc/convert-host.js';
 
+function toMathMl(code: string): HTMLElement {
+	const rendered = katex.renderToString(code, {
+		throwOnError: false,
+		output: 'mathml',
+	});
+	return JSDOM.fragment(rendered).querySelector('math');
+}
+
 // Transforms MFM to HTML, given the MFM text and a list of user IDs that are
 // mentioned in the text. If the list of mentions is not given, all mentions
 // from the text will be extracted.
@@ -98,15 +107,11 @@ export async function toHtml(mfmText: string, mentions?: string[]): Promise<stri
 		},
 
 		async mathInline(node) {
-			const el = doc.createElement('code');
-			el.textContent = node.props.formula;
-			return el;
+			return toMathMl(node.props.formula);
 		},
 
 		async mathBlock(node) {
-			const el = doc.createElement('code');
-			el.textContent = node.props.formula;
-			return el;
+			return toMathMl(node.props.formula);
 		},
 
 		async link(node) {