Abstract: The present invention relates to a portable air pump, where such including a housing, which is provided with an air inlet and an air outlet. The housing is provided with centrifugal fan blades, a motor that drives the centrifugal fan blades to rotate, and a battery to power the motor. An air outlet duct is formed between the air inlet and the air outlet, and the motor and battery are built into the air outlet duct. The present invention has the advantages: by setting up an air outlet duct between the air inlet and the air outlet of the housing, and directly embedding the centrifugal fan blades, motor, battery and other drive components into the air outlet duct, the fan blade cavity and the drive cavity are directly connected to form the same duct, and the air flow generated by the air outlet duct is directly used for rapid heat dissipation, which further enhances the heat dissipation effect, and also improves the endurance and performance of the air pump.