diff --git a/netwerk/dns/TRR.cpp b/netwerk/dns/TRR.cpp
index 1d0cd5e1142f..0572da4723f0 100644
--- a/netwerk/dns/TRR.cpp
+++ b/netwerk/dns/TRR.cpp
@@ -882,6 +882,28 @@ void TRR::ReportStatus(nsresult aStatusCode) {
   }
 }
 
+static void RecordHttpVersion(nsIHttpChannel* aHttpChannel) {
+  nsAutoCString protocol;
+  nsresult rv = aHttpChannel->GetProtocolVersion(protocol);
+  if (NS_FAILED(rv)) {
+    LOG(("Failed to get protocol version, rv=%x", (int)rv));
+    return;
+  }
+
+  if (protocol.LowerCaseEqualsLiteral("h2")) {
+    Telemetry::AccumulateCategorical(
+        Telemetry::LABELS_DNS_TRR_HTTP_VERSION::h_2);
+  } else if (protocol.LowerCaseEqualsLiteral("h3")) {
+    Telemetry::AccumulateCategorical(
+        Telemetry::LABELS_DNS_TRR_HTTP_VERSION::h_3);
+  } else {
+    Telemetry::AccumulateCategorical(
+        Telemetry::LABELS_DNS_TRR_HTTP_VERSION::h_1);
+  }
+
+  LOG(("DoH endpoint responded using HTTP version: %s", protocol.get()));
+}
+
 NS_IMETHODIMP
 TRR::OnStopRequest(nsIRequest* aRequest, nsresult aStatusCode) {
   // The dtor will be run after the function returns
@@ -927,6 +949,7 @@ TRR::OnStopRequest(nsIRequest* aRequest, nsresult aStatusCode) {
       if (NS_SUCCEEDED(rv) && UseDefaultServer()) {
         RecordReason(nsHostRecord::TRR_OK);
         RecordProcessingTime(channel);
+        RecordHttpVersion(httpChannel);
         return rv;
       }
     } else {
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index 169a94079b90..7036408a19fe 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -4220,6 +4220,17 @@
     "n_buckets": 50,
     "description": "Time from the last received byte of the response until we have notified the consumer with a DNS record (msec)"
   },
+  "DNS_TRR_HTTP_VERSION": {
+    "record_in_processes": ["main"],
+    "products": ["firefox"],
+    "expires_in_version": "never",
+    "kind": "categorical",
+    "labels": ["h_1", "h_2", "h_3"],
+    "releaseChannelCollection": "opt-out",
+    "alert_emails": ["nhnt11@mozilla.com", "necko@mozilla.com"],
+    "bug_numbers": [1460314],
+    "description": "HTTP version used by DoH endpoint"
+  },
   "DNS_NATIVE_LOOKUP_TIME": {
     "record_in_processes": ["main"],
     "products": ["firefox", "fennec"],