Forty Ossimi early weaned male lambs (8 weeks old age and 12.86 kg live body weight) were used in a study for 32 wks to investigate the effect of dietary roughage sources and levels during growing and finishing periods on lambs performance and carcass characteristics. At the beginning of 9th week, animals were randomly assigned into four nutritional treatments (each of 10 animals), while a starter ration 15.87 % DCP and 85.23 % TDN was prepared to serve as a control diet during the 1st period. The experimental study included two feeding periods. In the first period (12 weeks), roughage sources i.e. Peanut hulls (PH), sugarcane bagasse (SCB) and ground corn cobs (Ccb) were incorporated at 10 % to substitute 10 % corn grains in the control diet to attain three isonitrogenous and caloric rations (16.65 % DCP & 82.40 % TDN). In the second period, roughage levels were increased to 40% from rations composition to attain (13.21 CP and 64.07 TDN %). Metabolic trials were conducted by the end of each feeding period. By the end of the finishing period, 12 randomly slaughtered animals were dressed to justify carcass traits and meet chemical composition. Results obtained indicated that dietary roughage sources and levels didn't affect significantly lambs growth performance during the two feeding periods. However, lambs raised on both (Ccb) and (SCB) rations showed higher (p<0.05) feed conversion ratios, lower (p<0.05) feed costs and higher (p<0.05) net profit returns by the end of the finishing period. Growth performance during the whole period (32wks), pointed out to insignificant difference among groups. Results of carcass characteristics revealed that dietary roughage sources neither affect significantly hot carcass weight nor edible offal organs, however lambs offered (Ccb) ration showed relatively higher insignificant hot carcass weight in compare with the other tested roughages. Dietary roughage sources didn't have any significant influences on the chemical composition of eye muscle tissues (longismus dorsi).