Three experiments were conducted to investigate effects of dietary energy and protein levels on performance of laying hens. A total of 360 hens each of 352-day old Manina Brown (Exp.1), 280-day old Brown Warren (Exp.2) or 3174ay old Brown Warren (Exp.3) was divided into 20 pens of 18 birds. Each pen was assigned to one of the four dietary treatments with 5 replications according to a 2${ imes}$2 factorial design, consisting of all possible cominations of two levels of metabolizable energy (2,500 and 2,800 kcal/kg of diet) and two levels of crude Protein (13 and 16%). All hens were housed two birds per cage. Exp.1 and 2 were conducted for four weeks and hens were fed experimental diets ad libitum, and Exp.3 lasted two weeks and feed consumption was restricted to 130g/hen/day. In Exp.1 and 2, increasing either energy or protein level in the diet numberically improved egg production. However, in Exp. 3, where feed consumption was restricted, egg Production was affected significantly 〈0.05) by the energy levies and numerically by the protein levels. Neither protein nor energy level influenced egg weight in Exp. 1 and 2, but in Exp. 3 the higher level of energy improved egg weight numerically, In all three experiments increasing either protein or energy level increased egg mass. Higher levels of either protein and energy tended to decrease feed consumption and improve feed conversion rate numerically. It should also be noted that the higher level of energy improved egg mass produced per unit intake of protein and the higher level of Protein improved egg mass produced per unit intake of energy.