A reciprocating pump includes: a housing with a fluid channel that includes a pump chamber; a reciprocated member that is disposed in the housing to form the pump chamber, and reciprocable for suction and discharge of fluid; an actuator configured to reciprocate the reciprocated member; and a pressure gauge with a pressure receiving portion, configured to detect pressure of the fluid in the fluid channel via the pressure receiving portion. The housing includes an inner wall facing the fluid channel, and a flexible, membranous portion placed continuously next to the inner wall to face the fluid channel. The pressure gauge is attached to the housing such that the membranous portion is sandwiched between the pressure receiving portion and the fluid channel.