Holstein Friensian crossbred male calves were used in studying the effects of three concentrate levels on growth rate, feed conversion ratio and carcass characteristics. The experiment utilized 12 male calves (10 weeks of age) which were divided into 3 treatments. From 10 to 38 weeks old animals in the first, second and third treatment recieved concentrate at 2.0, 2.5 and 3.0 kg/hd/d, respectively. After that animals in the first, second and third treatment recieved concentrate at 1%, 1.3% and 1.6% body weight until slaughter at 1 year old. All animals were provided with ad libitum of paragrass as roughage source throughout the experiment. Average daily gain of the first treatment (619.64 g/d) was significantly less than those from the second treatment (734.95 g/d) and the third treatment (715.39 g/d). (P<0.05). Total feed intake between treatment were not significant different (P>0.05). Feed conversion ratio of the second treatment (6.32) showed significantly lower as compared with the first (6.83) and the third treatment (6.68) (P<0.05). There was not significant difference in the percentage of dressed, lean, fat and bone among the 3 treatments (P>0.05). The average net income from animals in the second treatment was highest (1,010.94 Baht/head) and the first treatment was lowest (562.48 Baht/head)