This paper aimed to compare the milk yield of pure breed Turcana ewes and crossbreed F1 Lacaune x Turcana ewes during their first lactation. Growth performance of F1 Lacaune x Turcana crossbreed lambs and of purebreed Turcana lambs was registered, in both male and female lambs. Results shown the fact that, in 3 mounths of age male lambs, were registered an average body weight of 22.47 kg in pure Turcana breed, and of 23.46 kg in F1 crossbreed lambs. In female lambs, during their first 90 days, the average body weight was of 20.66 kg in purebreed Turcana and of 21.41 kg in F1 Lacaune x Turcana crossbreeds. During first lactation, milk yield of F1 Lacaune x Turcana ewes was on average of 152.74 liters, compared with first lactating Turcana ewes, witch produced an average of 116.80 liters. Differences registered between the two populations was of 35.94 liters (p<0.001). Both growth rate and milk yield are improved in indigenous Turcana sheep breed through utilization of Lacaune rams.