To provide a fluid transporting device capable of switching between pumps while keeping a constant delivery flow rate without interrupting delivery of a fluid during periodic inspection of the pumps as preventive maintenance.

A fluid transporting device 1 in which two rotary positive-displacement pumps 2A and 2B including the spare pump 2B, are connected to a fluid transporting system in parallel, includes a controller 9 for controlling motion of the pumps 2A and 2B. The controller 9, when, during an operation, switching the spare pump 2B to regular use and switching the pump 2A for regular use paired with the spare pump 2B to spare use, switches between the pumps while controlling rotational speeds R_A and R_B of the pumps 2A and 2B so that a total sum Q_SV of fluid flow rates Q_A and Q_B by the pumps 2A and 2B is always constant.