A bellows pump which is disclosed herein has two bellows made of a plastic material and provided with liquid inlet and outlet ports for transferring a liquid by expanding and contracting the bellows. The bellows pump comprises cylinder cases in each of which the bellows is vertically expandably and contractably contained and mounted at its access port side to a ceiling of said cylinder cases, gas pumping means for alternately feeding a compressed gas from a lower end thereof into the cylinder cases, a pair of rods passed through bottoms of the cylinder cases and fixed to the lower ends of the bellows, and adapted to be moved in response to the expansion and contraction of the bellows, and actuating means adapted to be operated in response to the up and down movement of the rods.
