Cyclic loading is common experimental practice for investigations of large structures like vehicles. Numerical analysis of cyclic loading conditions is also a well-established field of research and application. Theoretical and practical support is rare for evaluating growth of fatigue cracks under cyclic loading conditions. Cracks can occur naturally in engineered components due to combination of environmental effects and materials and geometric properties. In this study, the effects of heat treatment on crack initiation & propagation of stainless steel (SS-304) are investigated. The specimens are subjected to different cyclic load. The crack initiation & propagation and final fracture behavior are observed microscopically. The specimens are kept in the furnace at 500°C at a constant time 1 hour where cooling medium is used as air for heat treatment & the effects of heat treatment are investigated. The fatigue life of the tested specimen at 400MPa stress before & after heat treatment are 54900 cycles & 61000 cycles respectively. So, a better fatigue life is found after heat treatment.