The present study investigates the relations between distributions of strain with those of martensitic volume fraction around fatigue cracks in SUS304 stainless steel. Specimens having random pattern created by spraying on their surfaces were fatigued at room temperature (297K) in air. The pictures around fatigue crack were taken during fatigue crack propagation experiments. Distributions of strain were calculated by the digital image correlation (DIC) method with these pictures. Distributions of martensitic volume fraction Vα’ were measured around fatigue cracks with ferrite scope. The distributions of strain resembled those of Vα’. The higher the strain becomes, the more the α’ martensitic phase was induced by the plasticity-induced transformation around fatigue cracks. It was revealed that the same value of Vα’max is induced by strain regardless of static or fatigue.