The objective of this study was to evaluate the effect of sex class (castrated; non-castrated) and level of food restriction (0%, 30% and 60% of ad libitum consumption) on the quantitative composition of carcass and non-carcass components of Santa Ines lambs. A completely randomized 3x2 design (restriction level x sex class) was used to evaluate thirty lambs approximately two months of age with an average initial body weight of 13 ± 1.49 kg. When the average body weight of the animals in one of the treatment groups reached 28 kg, all animals were slaughtered. Sex class had effect on body weight at slaughter, empty body weight, hot carcass weight and cold carcass weight. The weight of the leg was greater in non-castrated animals. There was linear decreased effect according to increasing levels of restriction for the carcass cuts, except for leg and rear loin yield. There was statistic difference between sex class for the weights of kidneys, paw, and large intestine of non-castrated animals (P < 0.05). There was a negative linear association between level of food restriction and mass of blood, head, leather, paw, rumen, reticulum, abomasum, small intestine, large intestine; perirenal, omental, mesenteric and heart fat. The quantitative composition of carcass and non-carcass components of Santa Ines lambs is influenced by sex class and food restriction level.