Offlate all structural components are working in dynamic environment where the loads are harmonic or random in nature.Traditional design approach of testing hardware in those design environment prove to be costly and cumbersome. This paper describes the major fatigue analysis approaches applicable in evaluating fatigue life and damage of a structural component.Generally, fatigue analysis has two main methods, Strain life (Ɛ – N) and Stress life (S - N). These approaches are practically adopted in various real-time projects to predict the total design life of a structural component. The empirical relationship adopted in predicting the cycles to failure of a design using the stress-life and strain-life approaches is discussed in this paper.