Abstract-The authors are developing a subject-oriented environment of the spacecraft onboard equipment simulation modeling. This environment is basing on the Simulation Model Portability Standard, which determines the technology for compatibility and transferability of simulation models within big simulation projects of software-and-hardware complexes. We have designed a software architecture, proposed a division in software subsystems and described the main principles of their interaction. Our software extends the approaches provided by the standard with the original methods of information-graphic and intellectual modeling. Application of the simulation infrastructure allows to solve the tasks of acquisition, accumulation and diffusion of the space systems designers' experience and knowledge.