Abstract: In engineering practice, most engineering structures and mechanical parts are subjected to various forms of cyclic loads, and most of the load distributions exhibit multiple axial stress states. Under cyclic load, the study of multi-axis fatigue life is more close to engineering practice than that of uniaxial fatigue and has a wider application background. As for this situation, the research state of multi-axis fatigue life prediction methods in recent years was described in detail. The fundamentals, advantages and disadvantages of three major methods were introduced and compared:equivalent strain method, energy method and critical plane method. In addition, in view of the shortcomings of various multi-axial fatigue life methods at present, the future research work in multi-axial fatigue field was put forward.