diff --git a/src/reqs.c b/src/reqs.c
index 990152a..26158ae 100644
--- a/src/reqs.c
+++ b/src/reqs.c
@@ -267,6 +267,17 @@ establish_http_connection (struct conn_s *connptr, struct request_s *request)
                                       "Connection: close\r\n",
                                       request->method, request->path,
                                       request->host, portbuff);
+        } else if ((connptr->upstream_proxy) &&
+                (connptr->upstream_proxy->basic_auth)) {
+                /* Basic auth is set for upstream proxy. */
+                return write_message (connptr->server_fd,
+                                      "%s %s HTTP/1.0\r\n"
+                                      "Host: %s%s\r\n"
+                                      "Connection: close\r\n"
+                                      "Proxy-Authorization: Basic %s\r\n",
+                                      request->method, request->path,
+                                      request->host, portbuff,
+                                      connptr->upstream_proxy->basic_auth);
         } else {
                 return write_message (connptr->server_fd,
                                       "%s %s HTTP/1.0\r\n"