Abstract: A procedure of heat-fluid coupling finite element method is presented to simulate the thermal field of mass concrete with pipe cooling system, which can truly reflect the temperature gradient near the pipe and changes of water temperature along the pipe. Additionally, particle swarm optimization based on particle migration is adopted for parameter identification of Dittus-Boelter equation, to make it suitable for description of forced convection characteristic of pipe cooling. On the platform of ABAQUS, a user defined heat-fluid coupling element is given. A pouring block of Guandi concrete gravity dam is used for the verification of the heat-fluid coupling method and user defined element. The simulation results show that presented procedure is good to simulate the thermal field of the mass concrete with pipe cooling; at the same time the stress calculated by precise method is larger than the equivalent method.