The aim of this study was to use spreadsheet software (Excel) to solve linear programming models in formulating least cost rations of egg layers. The Ingredients used are corn, wheat, soybean meal, barley, wheat bran, protein concentrate, limestone, salt, dicalcuim phosphate, vitamin and mineral premix, vegetable oil. Results showed that the starter optimum ration for layers from (0 - 6) weeks, consist of these Ingredients (9.40, 26.91, 16.38, 38.71,' 4.51, 0.95, 1.09, 0.25, 1.18, 0.25, (Received April 18, 2009) (Accepted September 28, 2009) 0.33)% respectively and from (6-12) week of (0, 73.43, 8.72, 0, 14.37, 0, 0.99, 0.25, 1.39, 0.25, 0.57) % respectively, from (12-18) week (0, 78.36, 6.17, 0, 12.02, 0, 1.44, 0.25, 0.87, 0.25, 0.61)% respectively, from (18 week - start of production) (0, 15.55, 13.85, 0, 3.81, 0, 4.25, 0.25, 1.16, 0.25, 0.86 )% respectively, and during productive period from (0, 66.93, 10.62, 0,0, 9.09,9.01, 0.25, 3.82)% respectively, and the cost of these ration was 160.6, 130.70, 123.60, 145.22, 195.95) Iraqi Dinar/kg respectively. Results also show sensitivity report of allowable increase and decrease in ingredient cost and in constraint values and the shadow price.