Abstract: In order to realize the co-simulation of regional integrated energy，an integrated energy system with unified modeling and simulation platform is established，and a technical solution for cross-platform digital simulation technology is proposed.For its abundant thermodynamic component library，open source TRNSYS system is selected to build a integrated energy co-simulation platform with MATLAB/Simulink.The communication between TRNSYS and MATLAB is based on FMI technology，which integrates models established by different software at different levels of specification.It can meet the deeper simulation requirements of integrated energy.Taking a university in South China as the simulation scenario，a digital co-simulation model is built on the targeted platform to analysis the diversified energy demand including cooling，heating， powering and steam.Proven by the research，the muti-energy flow co-simulation technical route based on FMI technology is feasible，and the digital co-simulation of multiple energy can be realized by associating MATLAB with TRNSYS. The research achievement can be applied in more scenarios，and realize the digital co-simulation of software platform.It provides technical support for the hardware in the loop simulation，physical model simulation in the future.

Key words: FMI；TRNSYS；integrated energy system；muti-energy flow co-simulation；Combined Cooling, Heating and Power（CCHP）；regional integrated energy