Due to the multiple systems, multiple interfaces, narrow work site and tight construction schedule, the proper execution plan for the installation of the electrical and mechanical equipment is of great importance for the contractors of projects under BT mode. In the paper, the execution sequence of and interfaces among different systems are studied, so as to minimize the interference between different systems and to the protect the completed product. Conclusions drawn are as follows: 1) The execution sequence should be specified, the execution teams should be mobilized to the site according to the execution sequence in order, the working face delivery conditions, the working face delivery time and the interfaces and the working section division should be specified, which can ensure that the contractors can perform efficient working immediately after they are mobilized to the site; 2) Due to the proper execution of the electrical and mechanical works, the working efficiency is improved, the interference is avoided, the repeated dismantling and installation are minimized, the completed products and the equipment are well protected and the safety and the construction schedule are guaranteed.