To provide a liquid dispensing pump which hardly produces a sink mark on a valve seat part and smoothly performs a pushing-down operation of a stem.

An upper face-opening recessed channel 21 is peripherally provided on the upper face of a cylindrical piston 20 fitted in a cylinder so as to freely move vertically, and a stem 30 fitted so as not to be pulled out and so as to be freely movable vertically to the inner face of the upper part of the recessed channel is raised upward from the cylinder. A suction hole 42 is formed in a hanging cylinder 41 passing through the cylindrical piston 20 from the lower part of the stem and hanging, and an annular valve seat 43 with a communicating part is provided on the lower end of the hanging cylinder, to have a valve seat member 40 resiliently urging the annular valve seat upward. An upper face-opening fitting channel 47 is provided on the upper face of the annular valve seat 43, and a part of the cylindrical piston 20 is water-tightly fitted to the fitting channel. A lower face-opening sink mark preventive channel 48 is provided on the lower surface of the valve seat part being inside from the fitting channel, and the upper face of the sink mark preventive channel is positioned more upward than the lower surface of the fitting channel 47.

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