diff --git a/libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp b/libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp
index 201b9a3cce..954e003fb5 100644
--- a/libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp
+++ b/libraries/ESP8266WiFi/src/ESP8266WiFiSTA.cpp
@@ -121,7 +121,7 @@ wl_status_t ESP8266WiFiSTAClass::begin(const char* ssid, const char *passphrase,
     conf.threshold.authmode = AUTH_OPEN;
 
     if(passphrase) {
-        conf.threshold.authmode = AUTH_WPA_PSK;
+        conf.threshold.authmode = _useInsecureWEP ? AUTH_WEP : AUTH_WPA_PSK;
         if (strlen(passphrase) == 64) // it's not a passphrase, is the PSK, which is copied into conf.password without null term
             memcpy(reinterpret_cast<char*>(conf.password), passphrase, 64);
         else