Now society is faced with a big problem called stress. Stress can increase or decrease the hormones and body composition results in increased susceptibility to most diseases. Identifying compounds that are altered by stress and find out the impact of them in the body, in turn, are able to provide solutions to counter with the stress. This study is considered to impact of two different types of physical and psychological stress on corticosterone and peptide YY for greater recognition of them. Three groups of 12 mice of both sexes were randomly performed, control, group under physical stress and the last group under psychological stress (a hunter). At the end of study period blood samples were collected and plasma levels of corticosterone and peptide YY were measured. In our study, peptide YY levels negatively correlated with plasma corticosterone levels which indicate a stress-lowering effect of this peptide. Mice were under physical stress had significantly higher levels of corticosterone than the control group which it’s may indicate the impact of stressful factors. However, the mice that endured psychological stress have significantly higher corticosterone levels compared with the control group and with group under physical stress. As a result, with consider that the stressor factors period are the same for both groups, it can be concluded that the mice under psychological stress could not habituate to stressor factors so adaptation to psychological stress is much harder than getting used to physical stress.