The purpose of this study was to investigate the effectiveness of group therapy based on cognitive rehabilitation of memory and executive functions in TBI patients with moderating role of depression, anxiety and mental fatigue symptoms. The research design administrated was pretest- posttest experimental, during which 26 individuals with brain injury were chosen using purposive sampling method and randomly assigned to experimental (N=12) and control (N=14) groups. Data collection was done by the memory and executive functions package which is designed, translated and Customized by Hatami and colleagues (in press), as well as depression, anxiety and mental fatigue Questionaries’ and were then analyzed using by ANCOVA and MANCOVA. Intervention sessions were subsequently held for 12 sessions, each session two hours, two days a week, and the control group received routine hospital intervention. The results showed that rehabilitation exercises, improved semantic memory performance, problem solving and continuous attention in patients with TBI (p<0.05) but had no significant effect in divided attention, episodic and working memory (p>0.05). Individual differences, gender, age and tests low accuracy, may explain the lack of significant improvement in the patients with TBI. Also, the effectiveness of cognitive rehabilitation on the cognitive functions in general is related to mental fatigue changes, but there is no significant relationship in depression and anxiety changes and improvement of memory and executive function in people with brain injury.