The interaction of helium–vacancy (He–V) clusters with a gliding a/2<111>{110} edge dislocation in α-Fe is investigated by molecular dynamics methods under a constant strain rate at temperatures of 100–600K. A number of small He n V m (n/m=0–4) clusters initially placed at different positions relative to the slip plane are comparatively studied. The results show that the interaction of He–V clusters with gliding edge dislocations depends on the helium-to-vacancy (He/V) ratio, the position of the clusters relative to the slip plane, the cluster size, and also temperature. The obstacle strength of the He–V clusters relevant to the dislocation motion generally increases with increasing He/V ratio at the same temperature, but decreases slightly with increasing temperature for the same He–V cluster. One of the interesting results is that He–V clusters do not move along with the dislocation, even at 600K.