Abstract: The main forms of centrifugal pump flow regulation,including export valve control and pump variable speed control,are analyzed through the centrifugal pump and piping system characteristic curve diagram.The energy consumption loss of export valve control and pump variable -speed control is analyzed and compared through the characteristic curve diagram.This paper also points out that the flow regulation of centrifugal pumps with variable-speed control have better effects on saving energy and the energy-saving efficiency is related to the size of the flow changes.