A liquid feeding device includes a primary plunger pump; a secondary plunger pump connected downstream; a check valve provided between the primary plunger pump and the secondary plunger pump; a primary pressure sensor that detects a pressure in the pump chamber of the primary plunger pump; a liquid feeding control part configured to control operations of the primary plunger pump and the secondary plunger pump; and a liquid leakage detector configured to detect liquid leakage in the check valve based on a change in an output value of the primary pressure sensor during the waiting time. The liquid feeding control part is configured to control the operation of the primary plunger pump so that a waiting time, where the primary plunger pump stops without operating, is present while a discharge operation by the secondary plunger pump is performed after a suction by the primary plunger pump is completed.