diff --git a/src/material-experimental/mdc-autocomplete/autocomplete.spec.ts b/src/material-experimental/mdc-autocomplete/autocomplete.spec.ts
index 621e2d69855e..5448cbd10c57 100644
--- a/src/material-experimental/mdc-autocomplete/autocomplete.spec.ts
+++ b/src/material-experimental/mdc-autocomplete/autocomplete.spec.ts
@@ -2256,6 +2256,32 @@ describe('MDC-based MatAutocomplete', () => {
       componentOptions.slice(1).forEach(option => expect(option.deselect).not.toHaveBeenCalled());
     }));
 
+    it('should not reset the active item if the options list changes while open', fakeAsync(() => {
+      fixture.componentInstance.trigger.openPanel();
+      fixture.detectChanges();
+      zone.simulateZoneExit();
+      fixture.detectChanges();
+
+      const DOWN_ARROW_EVENT = createKeyboardEvent('keydown', DOWN_ARROW);
+      fixture.componentInstance.trigger._handleKeydown(DOWN_ARROW_EVENT);
+      fixture.detectChanges();
+      tick();
+
+      const classList = overlayContainerElement.querySelector('mat-option')!.classList;
+      expect(classList)
+        .withContext('Expected first option to be highlighted.')
+        .toContain('mat-mdc-option-active');
+
+      fixture.componentInstance.states.push({code: 'PR', name: 'Puerto Rico'});
+      fixture.detectChanges();
+      tick();
+      fixture.detectChanges();
+
+      expect(classList)
+        .withContext('Expected first option to stay highlighted.')
+        .toContain('mat-mdc-option-active');
+    }));
+
     it('should be able to preselect the first option', fakeAsync(() => {
       fixture.componentInstance.trigger.autocomplete.autoActiveFirstOption = true;
       fixture.componentInstance.trigger.openPanel();
@@ -2276,6 +2302,7 @@ describe('MDC-based MatAutocomplete', () => {
         testComponent.trigger.autocomplete.autoActiveFirstOption = true;
         testComponent.states[0].disabled = true;
         testComponent.states[1].disabled = true;
+        fixture.detectChanges();
         testComponent.trigger.openPanel();
         fixture.detectChanges();
         zone.simulateZoneExit();
diff --git a/src/material/autocomplete/autocomplete-trigger.ts b/src/material/autocomplete/autocomplete-trigger.ts
index b9312e8d2aec..bca3b0371524 100644
--- a/src/material/autocomplete/autocomplete-trigger.ts
+++ b/src/material/autocomplete/autocomplete-trigger.ts
@@ -527,7 +527,6 @@ export abstract class _MatAutocompleteTriggerBase
           // that were created, and flatten it so our stream only emits closing events...
           switchMap(() => {
             const wasOpen = this.panelOpen;
-            this._resetActiveItem();
             this.autocomplete._setVisibility();
             this._changeDetectorRef.detectChanges();
 
@@ -539,6 +538,7 @@ export abstract class _MatAutocompleteTriggerBase
               // can happen if the users opens the panel and there are no options, but the
               // options come in slightly later or as a result of the value changing.
               if (wasOpen !== this.panelOpen) {
+                this._resetActiveItem();
                 this.autocomplete.opened.emit();
               }
             }
@@ -653,6 +653,7 @@ export abstract class _MatAutocompleteTriggerBase
     // We need to do an extra `panelOpen` check in here, because the
     // autocomplete won't be shown if there are no options.
     if (this.panelOpen && wasOpen !== this.panelOpen) {
+      this._resetActiveItem();
       this.autocomplete.opened.emit();
     }
   }
diff --git a/src/material/autocomplete/autocomplete.spec.ts b/src/material/autocomplete/autocomplete.spec.ts
index ed41c3acbceb..fba6246ccf4c 100644
--- a/src/material/autocomplete/autocomplete.spec.ts
+++ b/src/material/autocomplete/autocomplete.spec.ts
@@ -2241,6 +2241,32 @@ describe('MatAutocomplete', () => {
       componentOptions.slice(1).forEach(option => expect(option.deselect).not.toHaveBeenCalled());
     }));
 
+    it('should not reset the active item if the options list changes while open', fakeAsync(() => {
+      fixture.componentInstance.trigger.openPanel();
+      fixture.detectChanges();
+      zone.simulateZoneExit();
+      fixture.detectChanges();
+
+      const DOWN_ARROW_EVENT = createKeyboardEvent('keydown', DOWN_ARROW);
+      fixture.componentInstance.trigger._handleKeydown(DOWN_ARROW_EVENT);
+      fixture.detectChanges();
+      tick();
+
+      const classList = overlayContainerElement.querySelector('mat-option')!.classList;
+      expect(classList)
+        .withContext('Expected first option to be highlighted.')
+        .toContain('mat-active');
+
+      fixture.componentInstance.states.push({code: 'PR', name: 'Puerto Rico'});
+      fixture.detectChanges();
+      tick();
+      fixture.detectChanges();
+
+      expect(classList)
+        .withContext('Expected first option to stay highlighted.')
+        .toContain('mat-active');
+    }));
+
     it('should be able to preselect the first option', fakeAsync(() => {
       fixture.componentInstance.trigger.autocomplete.autoActiveFirstOption = true;
       fixture.componentInstance.trigger.openPanel();
@@ -2261,6 +2287,7 @@ describe('MatAutocomplete', () => {
         testComponent.trigger.autocomplete.autoActiveFirstOption = true;
         testComponent.states[0].disabled = true;
         testComponent.states[1].disabled = true;
+        fixture.detectChanges();
         testComponent.trigger.openPanel();
         fixture.detectChanges();
         zone.simulateZoneExit();