Integrated Modular Avionics (IMA) system adopts a resource sharing architecture,which provides a more sophisticated and powerful avionics functionality,but also brings a more complex fault proliferation model at the same time.To solve this problem,we proposed a reliability assessment method based on Architecture Analysis and Design Language (AADL) and Generalized Stochastic Petri Nets (GSPN).Firstly,the system′s architecture and fault information were described with AADL language,and its AADL reliability model was established.To further analyze the dynamic behavior of its faults,the rule for transformation from AADL reliability model to GSPN model was studied,and IMA system reliability was assessed by analyzing the GSPN model.Finally,the effectiveness of this method was validated by reliability assessment of the display function of IMA system,and suggestions for selecting the architecture of display function were given via experimental comparison.