The multi agent model of resources conversion process have rising in 2 direction – simulation of processes and integration with artificial intelligent approaches (expert systems, situation and multi agent simulation) at now. In this work the main attention gave second direction that consist of knowledge representation research and integration with conceptual modeling for application in domain ontologies in decision support systems. The semantic network of multi agent resources conversion process was designed. The intelligent systems design method based on conceptual modeling, multi agent systems, simulation, expert and situation systems, object oriented approach was described. Model and method was implemented in software product BPsim. The software product was implemented in practice tasks.