This was conducted to determine the effects of body weight, organ weight, hematological values and biochemical parameters by L-carnitine (Carn) on the orchidectomized (Orch) rats. The animals were divided into 4 groups. Intact group (n=10) received no treatment and operation. Sham group (n=10) received only sham operation and no treatment. Orch group received operation and no treatment. Orch＋Carn received operation and L-carnitine. The body weights of each group increased, but that of the Orch＋Carn group were significantly lower than those in all the other groups. There were significant differences (P＜0.05, P＜0.001) of body weights between Orch＋Carn group and all the other groups. Also, organ weights such as heart, liver, spleen and kidney were measured. The heart weights were significantly lower (P＜0.001) in the Orch＋Carn group than those in Intact and Sham groups, respectively. The weights of liver and kidney in the Orch＋Carn group showed significant differences (P＜0.001) in comparison with those in all the other groups. Also, the spleen weights were significantly lower (P＜0.05) in the Orch＋Carn group than those in Intact and Sham groups, respectively. The hematological values of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were significant differences (P＜0.05, P＜0.01, P＜0.001) in comparison with those in all the other groups. On the other hand, the hematological values of white blood cell (WBC), red blood cell (RBC) and mean corpuscular hemoglobin concentration (MCHC) resulted in no significant differences in any other groups. The concentrations of total cholesterol (T-chol), triglyceride (TG) and high density lipoprotein (HDL) decreased significantly (P＜0.05) in the Orch＋Carn group as compared to those in the Orch group. We conclude that L-carnitine was significantly decreased the body weight in the orchidectomized rats. Our findings suggest that L-carnitine may influence the process of lipid packaging and absorption in the orchidectomized rats.