Overweight is one of the most important reasons for increasing the liver enzymes that causes liver and cardiovascular disease. The purpose of this research is to investigation the effects of 12weeks training on liver enzymes. Subjects of this research is 26 woman with BMI≥29 and average age Between 42 to 52, they divided to two main groups: experimental and control group n=13. 24 hours before training and 48 hours after sampling, body composition and oxygen maximum, were done for all of the subjects. Experimental group have done 12 weeks endurance training that contains 3 session between 40 to 80 percent of heart beat and duration of 15 to 30 min. Data was analyzed by using of covariance and T test,(a≤0./05),results showed that in experimental group there is significant increase in oxygen maximum (p=0/006) and significant decrease observed in BMI (p=0/001). But not observed significant change in ALT enzymes (p=0/493) and AST (p=0/403). Results showed that the impacts of 12 weeks endurance training on liver enzymes of those women was not significant because of not preparing of subjects, also high level of BMI in both groups are possible. Therefore, non significant increase of ALT exercise group be investigated, the longer half life of this enzyme is (40+12) hours. So, it seems that we need more than 48hours to recovery the enzyme.