Eight different morphometric dimensions were monitored on 106 lamb carcasses belonging to three Catalan meat sheep breeds (Ripollesa, Rousillon Red and Xisqueta). Our purpose was to examine differences with regard to measurable carcass dimensions and also to establish between and within breed relationships among the carcass components. Measured variables included: carcass weight (CW), leg length (LL), carcass internal length (IL), carcass length (CL), chest width (ChW), hip width (HW), chest depth (CD), leg circumference (LC) and chest circumference (CC). From these measurements seven indices were obtained. Roussillon Red carcasses were the shortest, with the largest leg capacity, the lowest corporal index and giving a sense of"squareness". Xisqueta carcasses presented the longest leg length. Ripollesa carcasses were the smallest in chest circumference. The rest of the variables were similar between breeds.