Abstarct: The aim of this study was to assess the effects of anabolic steroids Boldenone with eight weeks of endurance training and jujube extract on changes in the structure of liver in male Wistar rats. For this purpose, 42 male Wistar rats aged 8-6 weeks and the initial weight 204.24 ± 36.50g selected as samples and randomly divided into six groups: 1-control (no exercise-without steroids), 2 (injected steroids), 3- (endurance training + steroid injection), 4- (endurance training + steroid injection + jujube extract), 5 (jujube extract + steroid injections), 6 sham (no exercise + olive oil). After 8 weeks ethical methods euthanized and liver morphology was evaluated by light microscopy. Results showed that rats receiving Boldenone weight than the other groups were not significant. Stained sections from rat liver showed healthy control group, but the groups receiving the drug, liver damage, including vasculature, vacuoles of fat, inflammation and degeneration was observed. In the second group were more severe injuries. According to the findings, endurance training and jujube extract are not able to prevent liver damage caused by Boldenone. Therefore, athletes should anabolic steroids (including Boldenone) to increase performance, use.