The invention relates to a device for the pressure-based detection of a clot in an extracorporeal blood circuit. The device comprises at least one cyclically operating pump for pumping the liquid located in the extracorporeal circuit and at least one pressure sensor, which is arranged so as to ascertain the current pressure curve over time in the liquid pumped by the pump in a current pump cycle, wherein the device has at least one storage device in which at least one reference pressure curve is stored based on at least one pressure curve over time that has been ascertained in a pump cycle of the pump preceding the current pump cycle of the pump, and the device comprises at least one analysis unit which is designed to compare the current pressure curve with the reference pressure curve in a time-corresponding manner.
