To determine the relationship between biochemical parameters and production traits in sheep, 111 sheep raised in Bandirma Sheep Research Institute were used as living material. Blood samples of 31 Hampshire Down x Merino, 33 Dorset Down x Merino, 27 German Black Headed x Merino and 20 Border Leicester x Merino crosses were taken. The levels and types of blood glutathione (GSH) and erythrocyte potassium (K+) were determined. Correlations between some production traits such as greasy fleece weight and lamb birth weight were estimated. Statistical significance was found in greasy fleece weight and high glutathione (GSH(H)) and low potassium (LK) SBA x Merino crosses, but in Dorset Down x Merino crosses only low glutathione (GSH(h)) type was shown to have significance with regards lamb birth weight.