The aim of this study was to investigate the mediating role of self-knowledge process (integrative self-knowledge and mindfulness) and self control in regulating of relationship between perceived and objective stress and anxiety, depression, and physical symptoms. 217 firefighters were selected by simple stratified sampling from 22 stations. They responded to integrative self-knowledge (Ghorbani et al.,2008), mindfulness (Brown & Ryan.,2003), self control (Tangeny et al.,2004) perceived stress (Cohen et al., 1983) objective stress (made in this research), anxiety and depression(Costello & Comrey.,1967) scals  and symptoms check list(Bartone.,1995). The results showed the interaction between integrative self- knowledge and self control has the most role in regulating the relationship between perceived stress and anxiety, depression and physical symptoms. Objective stress influenced by perceived stress that emphasized on importance of subjectivity of stress.Finally, Findings indicate the mediating role of self-knowledge process in relationship between stress and anxiety, depression, and physical symptoms.