For the same transportation condition,the number of dredge pumps and the different speeds matching combination among pumps may affect the efficiency and fuel cost of dredge pumps.This situation is especially obvious for the dredge pumps driven by the variable frequency motor with a larger speed adjustment range.Aiming at this problem,we analyze the relevant characteristics of dredge pump,and the principle of dredge pump association and speed matching,take the fuel consumption rate as evaluation standard,and study the case of dredge pump association and speed matching under specific working conditions.The results show that there must be an optimal combination scheme of the number of dredge pumps and the speed of dredge pumps under a certain working condition,so as to save fuel oil.