Xilinx FPGA design tools Vivado support project based mode and none project mode, the project based mode is used by most of the designs with powerful graphical interface IDE, but none project mode also has its unique advantages and magical effect, this paper presents a method of post-synthesis simulation based on none project mode of Vivado, which can find errors early, such as the simulation result of module (pre-synthesis) is correct, but there are errors when added to compile the project or on board debugging, thus this method can save development time and improve work efficiency.