diff --git a/Formula/libpq.rb b/Formula/libpq.rb
index d5965bb459..0be14bf32e 100644
--- a/Formula/libpq.rb
+++ b/Formula/libpq.rb
@@ -1,8 +1,8 @@
 class Libpq < Formula
   desc "Postgres C API library"
   homepage "https://www.postgresql.org/docs/9.6/static/libpq.html"
-  url "https://ftp.postgresql.org/pub/source/v9.6.3/postgresql-9.6.3.tar.bz2"
-  sha256 "1645b3736901f6d854e695a937389e68ff2066ce0cde9d73919d6ab7c995b9c6"
+  url "https://ftp.postgresql.org/pub/source/v9.6.4/postgresql-9.6.4.tar.bz2"
+  sha256 "2b3ab16d82e21cead54c08b95ce3ac480696944a68603b6c11b3205b7376ce13"
 
   bottle do
     sha256 "fc7ee090e7864661f5f0d77a4d148ee2727ed48bb68ea1f6543ec2cbe60c7f71" => :sierra