An assembly optimal model combining with the immune genetic algorithm based on vaccine automatic updating (IGABVAU) was proposed to solve the assembly sequence plan problem (ASPP). According to assembly problem characteristic, four kinds of immune vaccines were proposed in which the KP and NL vaccines were set manually and the BP and NT vaccines were created automatically. The standard genetic algorithm (GA) and standard immune genetic algorithm (IGA) was compared by using a ship part assembly as an example. The result shows that the immune genetic algorithm based on vaccine automatic updating has a faster convergent speed. The KP and NL vaccines could improve the quality of assembly sequence population while the BP and NT vaccines could provide directions for next evolution.