The present invention relates to an equitime quantum correction and regulation method of calorimeter flow accuracy. It is characterized by that said invention uses the flow coefficient of the mechanical calorimeter as basis of flow measurement, and uses a standard flowmeter as standard for correcting flow measurement error; then the flow full-scale range of calorimeter can be divided into several different flow conditions, and the measurement collecting time t of every flow condition is equal time quantum, then the meter to be corrected and standard meter can be used for synchronously measuring every flow condition and two calculation formulas can be used to define the accumulated hot water volume for heating energy user. Said invention can make flow measurement error accuracy be controlled in 0.5%.