This study investigated the effect of different stocking density on behavior, body condition score and some blood parameters of male camels in the rut period. Thirty-six male dromedary camels in rut period weighing from 350 to 400 kg were randomly divided in to three stock densities, 3 [lower stocking density (75%) (LSD)], 4 [normal stocking density (100%)(NSD)], and 5 [higher stocking density (125%)(HSD)] camels on 60 m2 of pen, respectively. Behavioral observations were performed for 10 weeks once per week for posture, maintenance, aggressive and social behavior using instantaneous scan sampling. Blood samples were collected at the end of the experiment for some serum blood parameters (Total protein, Albumin, Globulin, and Albumin/Globulin ratio) and blood hormones (Cortisol, Testosterone, T3, T4, and T3/T4 ratio). The results indicated that, in comparison with LSD and NSD, HSD increased the aggressive behavior, standing duration and cortisol level (P < 0.05), while, it decreased the lying, walking, rumination, body condition score, testosterone, T3 and T4 level (P < 0.05). In addition, there were no significant effects on drinking behavior and blood parameters between all the treatments (P > 0.05). Conclusively, HSD in group rearing had a bad effect on aggression, body condition score and sexual performance of male camels in the rut period.