An engine of a working vehicle in which an adverse effect of oil temperature rise is avoided, by decreasing a load applied to an accelerator when the working vehicle moves while lifting a boom and approaches a place where the load in a bucket is to be dumped during dump approach and, reducing heat generated through operation of a brake, and deterioration in work efficiency of the working vehicle is avoided by preventing the lifting speed of a boom from decreasing. A hydraulic pump controller and a method for controlling the hydraulic pump are also provided. On conditions that a throttle amount sensor detects that an operation amount of an accelerator pedal is a prescribed threshold value (operation amount 70%) or higher, a brake pressure sensor detects that a brake unit is actuated (brake on), and a vehicle speed sensor detects that a body speed is a prescribed threshold value or higher, a transmission controller outputs a throttle correction order to decrease a target engine speed to a governor through an engine controller, and outputs to a pump control valve through a work equipment controller an order to change a swash plate angle at the time of lifting the boom to cover a decrease amount of a discharge flow rate of a hydraulic pump by the throttle correction order to maintain the discharge flow rate from the hydraulic pump.