The ICD simulation module included in design of the general avionics integrated processing system was improved by taking the Matlab/Simulink co-simulation flight model as simulation stimuli and making it interactive with the integrated processor.This method has the following advantages:1) the physical quantities received by the integrated processor is from the identically simulated flight model which makes the results of actual significance; and 2) the calculation results can be compared with the output of simultaneously algorithm of Matlab/Simulink to ease the debugging and verifying of the processors functional designation.