diff --git a/changelogs/unreleased/65700-document-max-replication-slots-pg-ha.yml b/changelogs/unreleased/65700-document-max-replication-slots-pg-ha.yml
new file mode 100644
index 00000000000..bacc3f5fc11
--- /dev/null
+++ b/changelogs/unreleased/65700-document-max-replication-slots-pg-ha.yml
@@ -0,0 +1,5 @@
+---
+title: Add max_replication_slots to PG HA documentation
+merge_request: 31534
+author:
+type: other
diff --git a/doc/administration/high_availability/database.md b/doc/administration/high_availability/database.md
index f7a1f425b40..7c9e02d889e 100644
--- a/doc/administration/high_availability/database.md
+++ b/doc/administration/high_availability/database.md
@@ -327,6 +327,7 @@ When installing the GitLab package, do not supply `EXTERNAL_URL` value.
    postgresql['sql_user_password'] = 'POSTGRESQL_PASSWORD_HASH'
    # Replace X with value of number of db nodes + 1
    postgresql['max_wal_senders'] = X
+   postgresql['max_replication_slots'] = X
 
    # Replace XXX.XXX.XXX.XXX/YY with Network Address
    postgresql['trust_auth_cidr_addresses'] = %w(XXX.XXX.XXX.XXX/YY)