Micromechanics mechanism of two α-Fe models with and without a/2〈111〉{110} edge dislocations is investigated under a constant strain rate of 109s−1 at 800K with 0.1at.% He by molecular dynamics simulations. The results show that micromechanics behaviors are tailored by pressure release of He clusters and subsequent He bubbles coalescence. Furthermore, it is interested to notice that yield stress and strain of the model with dislocations is 0.06 and 10.52GPa, which is lower than that of the model without dislocations (0.105 and 11.77GPa), respectively. The reason for the acceleration is attributed to the consolidation of positive and negative edge dislocations, which induces the nucleation and growth of larger He bubbles.