diff --git a/packages/material-ui-lab/src/Autocomplete/Autocomplete.test.js b/packages/material-ui-lab/src/Autocomplete/Autocomplete.test.js
index 2c43a6c21b3b98..f037fc72cc094b 100644
--- a/packages/material-ui-lab/src/Autocomplete/Autocomplete.test.js
+++ b/packages/material-ui-lab/src/Autocomplete/Autocomplete.test.js
@@ -814,6 +814,27 @@ describe('<Autocomplete />', () => {
       fireEvent.keyDown(document.activeElement, { key: 'Enter' });
       expect(handleChange.callCount).to.equal(1);
     });
+
+    it('should not delete exiting tag when try to add it twice', () => {
+      const handleChange = spy();
+      const options = ['one', 'two'];
+      const { container } = render(
+        <Autocomplete
+          defaultValue={options}
+          options={options}
+          onChange={handleChange}
+          freeSolo
+          renderInput={params => <TextField {...params} autoFocus />}
+          multiple
+        />,
+      );
+      fireEvent.change(document.activeElement, { target: { value: 'three' } });
+      fireEvent.keyDown(document.activeElement, { key: 'Enter' });
+      expect(container.querySelectorAll('[class*="MuiChip-root"]')).to.have.length(3);
+      fireEvent.change(document.activeElement, { target: { value: 'three' } });
+      fireEvent.keyDown(document.activeElement, { key: 'Enter' });
+      expect(container.querySelectorAll('[class*="MuiChip-root"]')).to.have.length(3);
+    });
   });
 
   describe('prop: onInputChange', () => {
diff --git a/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js b/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
index f3ba2747b2a7db..9b2b1e3de4d88f 100644
--- a/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
+++ b/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
@@ -430,7 +430,7 @@ export default function useAutocomplete(props) {
     setValue(newValue);
   };
 
-  const selectNewValue = (event, newValue) => {
+  const selectNewValue = (event, newValue, origin = 'option') => {
     if (multiple) {
       const item = newValue;
       newValue = Array.isArray(value) ? [...value] : [];
@@ -439,7 +439,7 @@ export default function useAutocomplete(props) {
 
       if (itemIndex === -1) {
         newValue.push(item);
-      } else {
+      } else if (origin !== 'freeSolo') {
         newValue.splice(itemIndex, 1);
       }
     }
@@ -597,7 +597,7 @@ export default function useAutocomplete(props) {
             // Allow people to add new values before they submit the form.
             event.preventDefault();
           }
-          selectNewValue(event, inputValue);
+          selectNewValue(event, inputValue, 'freeSolo');
         }
         break;
       case 'Escape':