A monitoring device is provided for monitoring a semiconductor-based switching element having a control input, a power input, and a power output. The monitoring device includes a charge carrier source for charging the control input of the switching element with electric charge carriers, and a measuring device for detecting a charge carrier drain from the control input of the switching element. The measuring device emits a warning signal if the charge carrier drain lies above a specified threshold value. A corresponding method for monitoring a semiconductor-based switching element is also provided.