diff --git a/packages/rest-explorer/src/rest-explorer.controller.ts b/packages/rest-explorer/src/rest-explorer.controller.ts
index 19d52dbf5f99..962469123309 100644
--- a/packages/rest-explorer/src/rest-explorer.controller.ts
+++ b/packages/rest-explorer/src/rest-explorer.controller.ts
@@ -21,6 +21,7 @@ const template = fs.readFileSync(indexHtml, 'utf-8');
 const templateFn = ejs.compile(template);
 
 export class ExplorerController {
+  private serverRootPath: string;
   private openApiSpecUrl: string;
 
   constructor(
@@ -29,11 +30,12 @@ export class ExplorerController {
     @inject(RestBindings.Http.REQUEST) private request: Request,
     @inject(RestBindings.Http.RESPONSE) private response: Response,
   ) {
+    this.serverRootPath = this.getServerRootPath(restConfig);
     this.openApiSpecUrl = this.getOpenApiSpecUrl(restConfig);
   }
 
   indexRedirect() {
-    this.response.redirect(301, this.request.url + '/');
+    this.response.redirect(301, this.serverRootPath + this.request.url + '/');
   }
 
   index() {
@@ -48,13 +50,24 @@ export class ExplorerController {
       .send(homePage);
   }
 
+  private getServerRootPath(restConfig: RestServerConfig): string {
+    const openApiConfig = restConfig.openApiSpec || {};
+    const servers = openApiConfig.servers || [];
+    let url = servers[0] ? servers[0].url : '';
+    // trim trailing '/' so we can safely append rooted paths to it
+    if (url.endsWith('/')) {
+      url = url.substring(0, url.length - 1);
+    }
+    return url;
+  }
+
   private getOpenApiSpecUrl(restConfig: RestServerConfig): string {
     const openApiConfig = restConfig.openApiSpec || {};
     const endpointMapping = openApiConfig.endpointMapping || {};
     const endpoint = Object.keys(endpointMapping).find(k =>
       isOpenApiV3Json(endpointMapping[k]),
     );
-    return endpoint || '/openapi.json';
+    return this.serverRootPath + (endpoint || '/openapi.json');
   }
 }
 
diff --git a/packages/rest-explorer/test/acceptance/rest-explorer.acceptance.ts b/packages/rest-explorer/test/acceptance/rest-explorer.acceptance.ts
index b8159fa2d15f..8e0c0f360ac2 100644
--- a/packages/rest-explorer/test/acceptance/rest-explorer.acceptance.ts
+++ b/packages/rest-explorer/test/acceptance/rest-explorer.acceptance.ts
@@ -71,13 +71,6 @@ describe('API Explorer (acceptance)', () => {
       const body = response.body;
       expect(body).to.match(/^\s*url: '\/apispec',\s*$/m);
     });
-
-    async function givenAppWithCustomRestConfig(config: RestServerConfig) {
-      app = givenRestApplication(config);
-      app.component(RestExplorerComponent);
-      await app.start();
-      request = createRestAppClient(app);
-    }
   });
 
   context('with custom RestExplorerConfig', () => {
@@ -109,8 +102,53 @@ describe('API Explorer (acceptance)', () => {
     }
   });
 
+  context('with custom server root', async () => {
+    beforeEach(async () => {
+      await givenAppWithCustomRestConfig({
+        openApiSpec: {
+          servers: [{url: '/external/proxy/root'}],
+        },
+      });
+    });
+
+    it('prepends server root path to OpenAPI path', async () => {
+      const response = await request.get('/explorer/').expect(200);
+      const body = response.body;
+      expect(body).to.match(
+        /^\s*url: '\/external\/proxy\/root\/openapi.json',\s*$/m,
+      );
+    });
+
+    it('prepends server root path to /explorer redirect', async () => {
+      await request
+        .get('/explorer')
+        .expect(301)
+        .expect('location', '/external/proxy/root/explorer/');
+    });
+
+    it('handles server root with trailing slash', async () => {
+      await givenAppWithCustomRestConfig({
+        openApiSpec: {
+          servers: [{url: '/external/proxy/root/'}],
+        },
+      });
+      const response = await request.get('/explorer/').expect(200);
+      const body = response.body;
+      expect(body).to.match(
+        /^\s*url: '\/external\/proxy\/root\/openapi.json',\s*$/m,
+      );
+    });
+  });
+
   function givenRestApplication(config?: RestServerConfig) {
     const rest = Object.assign({}, givenHttpServerConfig(), config);
     return new RestApplication({rest});
   }
+
+  async function givenAppWithCustomRestConfig(config: RestServerConfig) {
+    app = givenRestApplication(config);
+    app.component(RestExplorerComponent);
+    await app.start();
+    request = createRestAppClient(app);
+  }
 });