The overall calculation model and single computational model was built for the space triangle pipe truss of the gas turbine room roofing. The simplified model for the gas turbine room roofings truss bearing was analyzed, on the basis of using hinge connection, sliding connection, and two support restraint. This paper compared the calculation results of different simplified models for the gas turbine room roofings truss, and investigated the impact of truss support restraint, gas turbine rooms structural stiffness, roofings concrete slab, and trusss single beam calculation model, which could provide references for the engineering design.