Abstract: This paper presents a way to simulate the Single Event Upset effect of anti-radiation hardening VLSI internal memory. The generation, propagation, masking and capture of the single event effect of the DUT internal memory can be estimated by designing the single event effect propagation factor algorithm of the memory unit, and the contribution to the SEU cross section of the whole circuit can be evaluated. On this basis, the simulation software of automatic extraction calculation was developed, and the heavy ion test under the MBIST and Typical Function mode were carried out. The results of simulation and experiment have the same variation rule, while the error is less than an order of magnitude. It is shown that the method has a high simulation accuracy and can be applied to the single event effect simulation of VLSI.