A water pump cooler for CPU wherein coolant may efficiently perform heat exchange, comprising at least: at least a heat absorbing component, at least a heat-transfer water pump, at least a heat exchange component and connecting water pipes, wherein a closed loop is formed by the heat-transfer water pump, connecting water pipes and heat exchange component. The heat-transfer water pump is disposed above the heat absorbing component to serve as a cycle power source for the coolant. The heat-transfer water pump includes at least a water pump component, which includes at least a base plate and a plurality of rotor axial impeller sections and rotor centrifugal impeller sections. The coolant is driven by the rotor axial impeller sections to flow into the rotor centrifugal impeller sections, and is then thrown at a high speed by the rotor centrifugal impeller sections to the heat exchange component for efficient heat dissipation. In this way, the coolant may perform heat exchange at a high speed within the closed loop.