Abstract: Body-centered cubic tungsten and iron are two important first wall facing plasma material and first wall structure material for nuclear fusion reactor respectively, and have to endure heavy doses neutron radiation. During neutron irradiation, a large number of helium atoms tend to agglomerate into helium bubbles, leading to mechanical property deterioration of the materials. In this paper, the evolution mechanism of helium bubble under different simulation conditions was compared by comprehensively analyzing the literatures about the nucleation and growth mechanism of helium bubbles by first principles, molecular dynamics and Monte Carlo methods. The results show that internal defects such as grain boundary, dislocation, vacancy and external conditions such as temperature can affect the nucleation and growth mechanism of helium bubbles. In addition, suggestions for further development are given.