The study was carried out in the Poultry Research Laboratory of the Department of Nutrition and Animal Production of the College of Animal Science Fernando Costa campus, Pirassununga/SP, in the period of 56 days, composed of 2 cycles of 28 days. The aim of the present study was to evaluate the effects of feeding reduced-nutrient diets supplemented with emulsifier on their performance and egg quality. A total of 384 commercials Hisex White® layers were used at 70 weeks of age, housed in an experimental masonry shed. The birds were randomly distributed in six treatments of seven repetitions with eight birds each. The treatments consisted of: positive control, being a conventional diet without emulsifier supplementation (T1); negative control, being a conventional diet without emulsifier supplementation but with -50 kcal of energy (T2); positive control + 250g/ton of emulsifier (T3); negative control + 250g/ton of emulsifier (T4); positive control + 500g/ton of emulsifier (T5); negative control + 500g/ton of emulsifier (T6). The use of 500g/ton of emulsifier (T6) in the energy-reduced layers diet provided positive effects on egg production, egg weight, egg mass and percentage of saleable eggs. On the other hand, no emulsifier in the diet control with reduced energy (T2) resulted in worse egg production, feed intake, egg weight, egg mass and percentage of saleable eggs. Regarding egg quality, yolk color and shell thickness were negatively affected in the diet with energy reduction and supplemented with 500g/ton of emulsifier (T6), indicating that levels above 250g/ton of emulsifier in the diet compromise yolk color and shell thickness. Therefore, under experimental conditions it was possible to conclude that the inclusion of emulsifier in the diet of commercial layers provided better performance rates and external quality of eggs.