diff --git a/README.md b/README.md
index ba804c86..adf33ec6 100644
--- a/README.md
+++ b/README.md
@@ -140,7 +140,7 @@ The custom report page link.
 - Type: String
 - Default: N/A
 
-Path of the generated report html file. This file can be deployed in other Actions steps, but is not included in the artifact. If omitted, no html report is generated.  
+Path of the generated report html file. This file can be deployed in other Actions steps, but is not included in the artifact. If omitted, treated as `./report.html`.
 
 #### `artifact-name` (Optional)
 
diff --git a/src/config.ts b/src/config.ts
index 145c5f24..22076f0f 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -1,7 +1,7 @@
 import * as core from '@actions/core';
 import { statSync } from 'fs';
 import { ARTIFACT_NAME } from './constants';
-import { dirname } from 'path';
+import { join } from 'path';
 
 export interface Config {
   imageDirectoryPath: string;
@@ -88,13 +88,6 @@ const validateReportFilePath = (path: string | undefined) => {
   if (path === undefined || path === '') {
     return;
   }
-  try {
-    const s = statSync(dirname(path));
-    if (s.isDirectory()) return;
-    else throw null;
-  } catch (_) {
-    throw new Error(`'report-file-path' is not in a valid directory. Please specify path to report file.`);
-  }
 };
 
 function validateCommentReportFormat(format: string): asserts format is 'raw' | 'summarized' {
@@ -126,7 +119,15 @@ export const getConfig = (): Config => {
   const branch = core.getInput('branch') || 'reg_actions';
   const customReportPage = core.getInput('custom-report-page') || null;
   validateCustomReportPage(customReportPage);
-  const reportFilePath = core.getInput('report-file-path');
+  let reportFilePath = core.getInput('report-file-path');
+  if (!reportFilePath) {
+    reportFilePath = './report.html';
+  }
+  try {
+    if (statSync(reportFilePath).isDirectory()) {
+      reportFilePath = join(reportFilePath, './report.html');
+    }
+  } catch {}
   validateReportFilePath(reportFilePath);
   const commentReportFormat = core.getInput('comment-report-format') || 'raw';
   validateCommentReportFormat(commentReportFormat);