For facing severely aerodynamic and inner equipments’ heat environment, the preliminary design scheme of integrated thermal management system which determines the feasibility of aircraft design, needs to be rapidly simulated to judge its feasibility, in the aircraft design stage. The traditional 3D simulation method is time-consuming and hard to meet the needs of frequent iterations in this stage. The fast simulation platform of integrated thermal management system based on heat balance evaluation model with 1D heat transfering approximation and modularly packaging of heat source, heat transfer, thermal control and other simulation components, which can quickly form the thermal management program and take simulation, optimization or iteration. Example shows that building the simulation platform and completing calculation each only take a few hours and several minutes, so as to speed up the iteration speed of the thermal management system, and can form a better aircraft design scheme in the preliminary design stage.