Abstract: A simulator presented in this paper can be used for a heat exchanger network witharbitrary topologic structure. On the basis of advanced techniques and modern ap-proaches, it is able to calculate both inlet and outlet temperature as well as pressure dropof each exchanger of the network efficiently. Also the maximum pressure drop and theroutes can be determined by the simulator. In addition, a dedicated data management sys-tem is constructed, which has many functions, such as data input, data output, data,change, data store and data checking, etc.