diff --git a/.changeset/smooth-grapes-pay.md b/.changeset/smooth-grapes-pay.md
new file mode 100644
index 00000000..30657045
--- /dev/null
+++ b/.changeset/smooth-grapes-pay.md
@@ -0,0 +1,5 @@
+---
+'@hono/zod-openapi': patch
+---
+
+fix(zod-openapi): correctly handle path parameters in basePath
diff --git a/packages/zod-openapi/src/index.ts b/packages/zod-openapi/src/index.ts
index 59b905b6..e9e90c1f 100644
--- a/packages/zod-openapi/src/index.ts
+++ b/packages/zod-openapi/src/index.ts
@@ -638,7 +638,7 @@ export class OpenAPIHono<
             path: mergePath(
               pathForOpenAPI,
               // @ts-expect-error _basePath is private
-              app._basePath,
+              app._basePath.replaceAll(/:([^\/]+)/g, '{$1}'),
               def.route.path
             ),
           })
@@ -649,7 +649,7 @@ export class OpenAPIHono<
             path: mergePath(
               pathForOpenAPI,
               // @ts-expect-error _basePath is private
-              app._basePath,
+              app._basePath.replaceAll(/:([^\/]+)/g, '{$1}'),
               def.webhook.path
             ),
           })
diff --git a/packages/zod-openapi/test/index.test.ts b/packages/zod-openapi/test/index.test.ts
index 8d29402a..3d056832 100644
--- a/packages/zod-openapi/test/index.test.ts
+++ b/packages/zod-openapi/test/index.test.ts
@@ -1274,6 +1274,53 @@ describe('basePath()', () => {
     expect(res.status).toBe(200)
     expect(await res.json()).toEqual({ path: 'abc' })
   })
+
+  it('Should correctly handle path parameters in nested basePath', async () => {
+    const app = new OpenAPIHono()
+    const nested = new OpenAPIHono().basePath('/:param2')
+
+    nested.openapi(
+      createRoute({
+        method: 'get',
+        path: '/{param3}',
+        responses: {
+          200: {
+            description: 'Get message',
+          },
+        },
+      }),
+      (c) => {
+        return c.json({
+          param1: c.req.param('param1'),
+          param2: c.req.param('param2'),
+          param3: c.req.param('param3')
+        })
+      }
+    )
+
+    app.route('/:param1', nested)
+
+    const json = app.getOpenAPIDocument({
+      openapi: '3.0.0',
+      info: {
+        version: '1.0.0',
+        title: 'My API',
+      },
+    })
+
+    const paths = Object.keys(json.paths)
+
+    expect(paths).toStrictEqual(['/{param1}/{param2}/{param3}'])
+    expect(paths).not.toStrictEqual(['/{param1}/:param2/{param3}'])
+
+    const res = await app.request('/foo/bar/baz')
+    expect(res.status).toBe(200)
+    expect(await res.json()).toEqual({
+      param1: 'foo',
+      param2: 'bar',
+      param3: 'baz'
+    })
+  })
 })
 
 describe('With hc', () => {