The invention further relates to an apparatus and method for monitoring a peristaltic hose pump, in particular a peristaltic hose pump of an extracorporeal blood treatment device. The power consumed by the pump and/or the pressure in the tubing segment upstream or downstream of the pump is/are measured during operation of the pump and test signals I1(t), I2(t) which are associated with the individual displacement members are determined. The power or pressure signals associated with the individual displacement members significantly differ from each other during abnormal operation of the hose pump, but no significant differences can be recognized during normal operation of the pump.
