diff --git a/bin/main.js b/bin/main.js
index 3c6585776f..fc8ce647c0 100644
--- a/bin/main.js
+++ b/bin/main.js
@@ -134,7 +134,7 @@ export async function main(nodeProcess) {
           if (arg.indexOf('--') === 0) {
             opt = camelize(arg.replace(/^--(no-)?/, ''));
             if (!(opt in marked.defaults)) {
-              continue;
+              throw Error(`marked: unknown option '${arg}'`);
             }
             if (arg.indexOf('--no-') === 0) {
               options[opt] = typeof marked.defaults[opt] !== 'boolean'
diff --git a/test/unit/bin.test.js b/test/unit/bin.test.js
index 30fa726674..6fbdc4affc 100644
--- a/test/unit/bin.test.js
+++ b/test/unit/bin.test.js
@@ -146,6 +146,14 @@ describe('bin/marked', () => {
       stdout: '<h1>test</h1>',
     }));
   });
+
+  describe('options', () => {
+    it('reports an unknown long option', testInput({
+      args: ['--does-not-exist'],
+      stderr: 'marked: unknown option \'--does-not-exist\'',
+      code: 1,
+    }));
+  });
 });
 
 describe('exec', () => {