Fatigue behavior of AISI 304 austenitic stainless steel has been investigated by carrying out fatigue tests using AISI 304 austenitic stainless steel specimens with two different heat treatment conditions (solution treated and solution treated + sensitized condition). In addition to that the effect of fretting on fatigue behavior of AISI 304 stainless steel with these two different heat treatment conditions has been investigated. The results showed that the plain fatigue (with out fretting) behavior was highly influenced by heat treatment conditions. However the fretting fatigue behavior was not highly influenced by heat treatment conditions. The results were observed based on the crack initiation mechanisms.