The invention discloses a large pump station flow monitoring method based on multi-parameter coupling correction. The large pump station flow monitoring method based on multi-parameter coupling correction comprises the following steps: firstly, determining various factors which influence flow of a large pump station, and distributing corresponding sensors in a region of a pump assembly to acquire the various influence factors and flow measurement values; secondly, establishing a fuzzy synthetic evaluation model on the basis of the various influence factors, determining an evaluation grade result according to measurement values of the various influence factors and the fuzzy synthetic evaluation model, and taking the evaluation grade result as a degree correction grade of current flow of the pump assembly; and thirdly, establishing a set of interval grade background data which are the same as the amount of evaluation grades in the fuzzy synthetic evaluation model for historical data of excess flow of pump machines, selecting flow historical data with the corresponding grades from the set of background data as priori background according to the degree correction grades; and correcting the actual measurement values of the flow by a Bayesian priori algorithm. By the method, graded priori correction on measurement of excess flow of the pump machines is realized, and accuracy of measurement of the excess flow of the pump station is improved effectively.