The invention discloses a construction method of a multifunctional hydrological information graphical display component based on Flex. The construction method includes designing an entire frame of the multifunctional hydrological information graphical display component; designing and realizing an interface which is used for receiving hydrological data and additional attribute data and for inputting data for users; realizing a data analyzing function of the component, namely data inputted by the users and the additional attribute data, and realizing analyzing and processing of the inputted data; realizing a dynamic generating function of a hydrological information graphical display interface; and performing interacting between the users and the component, and exporting the hydrological information in a graphical manner. By the aid of the construction method, a mechanism is provided for the users to know current hydrological information timely and directly, displaying, analyzing and comparing capacities of the hydrological information are improved, and the construction method can be widely applied in business systems of water scheduling, flood and drought resistances, demand irrigation and the like of Flex development.