diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index e0dd6991ab..abfcc3a15b 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -48,6 +48,8 @@
 *   Effect:
 *   Muxers:
 *   IMA extension:
+    *   Fix issue where DASH and HLS ads without the appropriate file extension
+        can't be played.
 *   Session:
     *   Put the custom keys and values in `MediaMetadataCompat` to
         `MediaMetadata.extras`
diff --git a/libraries/exoplayer_ima/src/main/java/androidx/media3/exoplayer/ima/AdTagLoader.java b/libraries/exoplayer_ima/src/main/java/androidx/media3/exoplayer/ima/AdTagLoader.java
index cf99362415..a0409dddde 100644
--- a/libraries/exoplayer_ima/src/main/java/androidx/media3/exoplayer/ima/AdTagLoader.java
+++ b/libraries/exoplayer_ima/src/main/java/androidx/media3/exoplayer/ima/AdTagLoader.java
@@ -183,6 +183,9 @@ import java.util.Map;
   /** Whether IMA has been notified that playback of content has finished. */
   private boolean sentContentComplete;
 
+  /** The MIME type of the ad pod that is next requested via an {@link AdEventType#LOADED} event. */
+  @Nullable private String pendingAdMimeType;
+
   // Fields tracking the player/loader state.
 
   /** Whether the player is playing an ad. */
@@ -775,6 +778,9 @@ import java.util.Map;
         String message = "AdEvent: " + adData;
         Log.i(TAG, message);
         break;
+      case LOADED:
+        pendingAdMimeType = adEvent.getAd().getContentType();
+        break;
       default:
         break;
     }
@@ -981,6 +987,10 @@ import java.util.Map;
     }
 
     MediaItem.Builder adMediaItem = new MediaItem.Builder().setUri(adMediaInfo.getUrl());
+    if (pendingAdMimeType != null) {
+      adMediaItem.setMimeType(pendingAdMimeType);
+      pendingAdMimeType = null;
+    }
     adPlaybackState =
         adPlaybackState.withAvailableAdMediaItem(
             adInfo.adGroupIndex, adInfo.adIndexInAdGroup, adMediaItem.build());
diff --git a/libraries/exoplayer_ima/src/test/java/androidx/media3/exoplayer/ima/ImaAdsLoaderTest.java b/libraries/exoplayer_ima/src/test/java/androidx/media3/exoplayer/ima/ImaAdsLoaderTest.java
index 895ae72f8e..8523ebad3c 100644
--- a/libraries/exoplayer_ima/src/test/java/androidx/media3/exoplayer/ima/ImaAdsLoaderTest.java
+++ b/libraries/exoplayer_ima/src/test/java/androidx/media3/exoplayer/ima/ImaAdsLoaderTest.java
@@ -283,6 +283,31 @@ public final class ImaAdsLoaderTest {
         adsMediaSource, /* adGroupIndex= */ 0, /* adIndexInAdGroup= */ 0, new IOException());
   }
 
+  @Test
+  public void loadAd_withAdContentTypeSet_setsMimeTypeInAdPlaybackState() {
+    // Load the preroll ad with content type set. Intentionally use all lower-case HLS MIME type as
+    // this is what the IMA SDK sets.
+    when(mockPrerollSingleAd.getContentType()).thenReturn("application/x-mpegurl");
+    imaAdsLoader.start(
+        adsMediaSource, TEST_DATA_SPEC, TEST_ADS_ID, adViewProvider, adsLoaderListener);
+
+    adEventListener.onAdEvent(getAdEvent(AdEventType.LOADED, mockPrerollSingleAd));
+    videoAdPlayer.loadAd(TEST_AD_MEDIA_INFO, mockAdPodInfo);
+
+    // Verify that the preroll ad has been marked with the expected MIME type.
+    assertThat(getAdPlaybackState(/* periodIndex= */ 0))
+        .isEqualTo(
+            new AdPlaybackState(TEST_ADS_ID, /* adGroupTimesUs...= */ 0)
+                .withContentDurationUs(CONTENT_PERIOD_DURATION_US)
+                .withAdCount(/* adGroupIndex= */ 0, /* adCount= */ 1)
+                .withAvailableAdMediaItem(
+                    /* adGroupIndex= */ 0,
+                    /* adIndexInAdGroup= */ 0,
+                    TEST_MEDIA_ITEM.buildUpon().setMimeType(MimeTypes.APPLICATION_M3U8).build())
+                .withAdDurationsUs(new long[][] {{TEST_AD_DURATION_US}})
+                .withAdResumePositionUs(/* adResumePositionUs= */ 0));
+  }
+
   @Test
   public void playback_withPrerollAd_marksAdAsPlayed() {
     // Load the preroll ad.