Steel in fuel-grade-ethanol (FGE) under cyclic load environment lead to fracture.

Crack initiation occurs even in constant load, but propagation needs cyclic load.

Increase of Cl^－ contents in FGE promotes environmentally assisted cracking on steel under cyclic load environment.

FGE-EAC under cyclic load shows mixture of intergranular and transgranular modes.

An environmentally assisted cracking mechanism by repeat of anodic dissolution and film regeneration is proposed.