diff --git a/packages/unified-latex-util-parse/README.md b/packages/unified-latex-util-parse/README.md
index bdfd2e3b..728682a2 100644
--- a/packages/unified-latex-util-parse/README.md
+++ b/packages/unified-latex-util-parse/README.md
@@ -160,6 +160,21 @@ function parseMinimal(str: String): Ast.Root;
 | :---- | :------- |
 | str   | `String` |
 
+## `getParser(PluginOptions)`
+
+Returns the default `unified-latex` parser if the argument is `undefined`, or
+create a new one with the provided `unifiedLatexFromString` options.
+
+```typescript
+function getParser(options?: PluginOptions): FrozenProcessor<Ast.Root, Ast.Root, Ast.Root, void>;
+```
+
+**Parameters**
+
+| Param  | Type            |
+| :----- | :-------------- |
+| option | `PluginOptions` |
+
 # Types
 
 ## `PluginOptions`
diff --git a/packages/unified-latex-util-parse/libs/parse.ts b/packages/unified-latex-util-parse/libs/parse.ts
index cb39696f..f5412383 100644
--- a/packages/unified-latex-util-parse/libs/parse.ts
+++ b/packages/unified-latex-util-parse/libs/parse.ts
@@ -1,8 +1,9 @@
 import * as Ast from "@unified-latex/unified-latex-types";
-import { unified } from "unified";
+import { type FrozenProcessor, unified } from "unified";
 import { unifiedLatexFromString } from "./plugin-from-string";
+import type { PluginOptions } from "./plugin-from-string";
 
-const parser = unified().use(unifiedLatexFromString).freeze();
+let parser = unified().use(unifiedLatexFromString).freeze();
 
 /**
  * Parse the string into an AST.
@@ -10,3 +11,18 @@ const parser = unified().use(unifiedLatexFromString).freeze();
 export function parse(str: string): Ast.Root {
     return parser.parse(str);
 }
+
+/**
+ * Returns the default `unified-latex` parser, or create a new one with the
+ * provided `unifiedLatexFromString` options
+ * @param options Plugin options of `unifiedLatexFromString` plugin.
+ * @returns The default `unified-latex` parser if `options` is `undefined`, or a
+ * newly created `unified-latex` parser with the provided `options`.
+ */
+export function getParser(
+    options?: PluginOptions
+): FrozenProcessor<Ast.Root, Ast.Root, Ast.Root, void> {
+    return options
+        ? unified().use(unifiedLatexFromString, options).freeze()
+        : parser;
+}