diff --git a/libtransmission/web.cc b/libtransmission/web.cc
index 48fbcb835..2a95492ad 100644
--- a/libtransmission/web.cc
+++ b/libtransmission/web.cc
@@ -536,8 +536,10 @@ public:
         {
             (void)curl_easy_setopt(e, CURLOPT_CAINFO, NULL);
             (void)curl_easy_setopt(e, CURLOPT_CAPATH, NULL);
+#if LIBCURL_VERSION_NUM >= 0x073400 /* 7.52.0 */
             (void)curl_easy_setopt(e, CURLOPT_PROXY_SSL_VERIFYHOST, 0L);
             (void)curl_easy_setopt(e, CURLOPT_PROXY_SSL_VERIFYPEER, 0L);
+#endif
         }
         else if (!std::empty(curl_ca_bundle))
         {