Aiming at the credibility evaluation of live-virtual-constructive (LVC) co-simulation, the architecture, model composition, application direction and simulation process of LVC co-simulation system are analyzed in depth. Combining the model verification in the system construction phase with the analysis and evaluation in the simulation application phase, a set of practical technical framework for simulation credibility evaluation is proposed, and the implementation method and process of credibility evaluation are given with a specific case to realize the quantitative evaluation of LVC co-simulation credibility. The application results show that the method can integrate the experience and knowledge of experts in the field, objectively reflect the credibility of the simulation system, and form a quantitative evaluation conclusion consistent with the expert cognition, which can effectively support the improvement of simulation credibility and the exertion of application benefits.