分析了传统CPM和PERT方法的缺陷，利用逻辑矩阵“穷举”识别工作路径，导出项目计划可靠性公式，提出了在两点法基础上确定时间参数、基于MATLAB+SIMULINK建立随机网络模型的解决方案。仿真分析表明，基于两点法的随机网络计划模型，建模简便易行，对于复杂系统和大型项目计划具有实际意义。In this article we discuss the stability problem of project planning. The first one is recognizing the access of the work through logic matrix. Second is reducing the project planning reliability formulations, the third one is putting forward the time parameters based on two points method. With them, a solution to the random network models which are based on MATLAB+SIMULINK can be obtained.