diff --git a/scripts/setup/pgroonga-config b/scripts/setup/pgroonga-config
index 1e95f1ebf8..f2f9dd4112 100755
--- a/scripts/setup/pgroonga-config
+++ b/scripts/setup/pgroonga-config
@@ -3,7 +3,6 @@ set -eux
 
 dbversion=$(crudini --get /etc/zulip/zulip.conf postgresql version)
 dbname=$(crudini --get /etc/zulip/zulip.conf postgresql database_name 2>/dev/null || echo zulip)
-dbuser=$(crudini --get /etc/zulip/zulip.conf postgresql database_user 2>/dev/null || echo zulip)
 
 sharedir="${1:-/usr/share/postgresql/$dbversion}"
 applied_file="$sharedir/pgroonga_setup.sql.applied"
@@ -11,7 +10,7 @@ applied_file="$sharedir/pgroonga_setup.sql.applied"
 installed_version=$(dpkg-query --show --showformat='${Version}' "postgresql-$dbversion-pgdg-pgroonga")
 
 if [ ! -f "$applied_file" ]; then
-    sql="CREATE EXTENSION PGROONGA; GRANT USAGE ON SCHEMA pgroonga TO $dbuser"
+    sql="CREATE EXTENSION PGROONGA"
 else
     sql="ALTER EXTENSION pgroonga UPDATE"
 fi