The present invention obtains a hydraulic pressure control unit capable of appropriately detecting abnormality in a hydraulic pressure control unit.

In a hydraulic pressure control unit (5) according to the present invention, a controller (52) includes a diagnosis section that executes a diagnostic mode to diagnose presence or absence of abnormality in the hydraulic pressure control mechanism (51) on the basis of a current fluctuation of a motor (35) in a state where a pump (34) is driven by the motor (35).