diff --git a/device/win_usb/win_usb.cpp b/device/win_usb/win_usb.cpp
index 5f03f8f..7235243 100644
--- a/device/win_usb/win_usb.cpp
+++ b/device/win_usb/win_usb.cpp
@@ -471,6 +471,7 @@ void usb_device::clear(void)
             {
                 if (cfg_desc_[i]->usb_if[j].altsetting->endpoint)
                     delete[] cfg_desc_[i]->usb_if[j].altsetting->endpoint;
+                delete cfg_desc_[i]->usb_if[j].altsetting;
             }
             delete[] cfg_desc_[i]->usb_if;
         }