A method for evaluating the corrosion-fatigue life of a steel material includes: bringing a corrosive medium into contact with a predetermined portion of the steel material; measuring strain on the steel material while applying cyclic loads to the steel material; measuring an N-th strain index from strain amplitude at the number of initial load applications and strain amplitude at the N-th load application (N is a natural number larger than the number of initial load applications); and estimating the corrosion-fatigue life of the steel material by comparing the N-th strain index with a previously certified life strain index.