A method for monitoring a contacting of electrodes of an ECG measuring devices is provided. At least three signals each from a first and a second input signal are generated. The first and the second input signal emanate from different electrodes and each electrode supplies one of the input signals to at least two of the signals generated by a first signal processing unit. The three signals are compared with a reference value. Inadequately contacted electrodes are identified based on the comparisons and are displayed. A monitoring device for implementing the method is provided. The monitoring device comprises a first signal processing unit connected to the electrodes at an input side, a second signal processing unit for identifying the inadequately contacted electrodes by receiving and processing at least three signals generated by the first signal processing unit, and a display unit for displaying the inadequately contacted electrodes.