diff --git a/builtin/gc.c b/builtin/gc.c
index b315b2ad58..54bae7f0c4 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -897,6 +897,12 @@ static int maintenance_task_prefetch(struct maintenance_run_opts *opts)
 	struct string_list_item *item;
 	struct string_list remotes = STRING_LIST_INIT_DUP;
 
+	git_config_set_multivar_gently("log.excludedecoration",
+					"refs/prefetch/",
+					"refs/prefetch/",
+					CONFIG_FLAGS_FIXED_VALUE |
+					CONFIG_FLAGS_MULTI_REPLACE);
+
 	if (for_each_remote(append_remote, &remotes)) {
 		error(_("failed to fill remotes"));
 		result = 1;
diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh
index 1074009cc0..f9031cbb44 100755
--- a/t/t7900-maintenance.sh
+++ b/t/t7900-maintenance.sh
@@ -149,7 +149,31 @@ test_expect_success 'prefetch multiple remotes' '
 	git log prefetch/remote2/two &&
 	git fetch --all &&
 	test_cmp_rev refs/remotes/remote1/one refs/prefetch/remote1/one &&
-	test_cmp_rev refs/remotes/remote2/two refs/prefetch/remote2/two
+	test_cmp_rev refs/remotes/remote2/two refs/prefetch/remote2/two &&
+
+	test_cmp_config refs/prefetch/ log.excludedecoration &&
+	git log --oneline --decorate --all >log &&
+	! grep "prefetch" log
+'
+
+test_expect_success 'prefetch and existing log.excludeDecoration values' '
+	git config --unset-all log.excludeDecoration &&
+	git config log.excludeDecoration refs/remotes/remote1/ &&
+	git maintenance run --task=prefetch &&
+
+	git config --get-all log.excludeDecoration >out &&
+	grep refs/remotes/remote1/ out &&
+	grep refs/prefetch/ out &&
+
+	git log --oneline --decorate --all >log &&
+	! grep "prefetch" log &&
+	! grep "remote1" log &&
+	grep "remote2" log &&
+
+	# a second run does not change the config
+	git maintenance run --task=prefetch &&
+	git log --oneline --decorate --all >log2 &&
+	test_cmp log log2
 '
 
 test_expect_success 'loose-objects task' '