计量泵 （英语：metering pump，proportional pump）往复泵的一种，利用往复泵流量固定的特点而发展起来的。可以用电动机带动偏心轮从而实现柱塞的往复运动。偏心轮的偏心度可以调整，柱塞的冲程就发生变化，以此来实现流量的调节。 计量泵主要应用在一些要求精确地输送液体至某一设备的场合，或将几种液体按精确的比例输送。如化学反应装置一种或几种催化剂的投放，后者是靠分别调节多缸计量泵中每个活塞的行程来实现的。

A metering pump moves a precise volume of liquid in a specified time period providing an accurate flow rate. Delivery of fluids in precise adjustable flow rates is sometimes called metering. The term "metering pump" is based on the application or use rather than the exact kind of pump used, although a couple types of pumps are far more suitable than most other types of pumps.