Reducing the energy content of broiler diets could lead to the formulation of diets with reduced production cost. Dimethylgycine (DMG) has been used as a dietary supplement to enhance dietary fat utilization in poultry. The objective of the present study was to investigate the effects of DMG supplementation in reduced energy diets on performance and nutrient digestibility in broiler chickens. Four hundred and eighty day-old broilers were randomly allocated to three dietary treatments: a standard energy diet (PC treatment), a reduced energy diet by 66 kcal/kg (NC treatment) and the reduced energy diet supplemented with 500 mg/kg of DMG (DMG treatment). Fat digestibility was significantly higher in DMG group, compared to PC and NC groups. Intestines and gizzard lesion scores were found to be lower in the DMG group compared to PC. DMG supplementation resulted in lower jejunum pH and ileum viscosity in broilers. Overall, the present study showed that DMG supplementation in reduced energy broiler diets restored growth performance to the levels obtained with a standard diet. This result was probably mediated by the positive effects on the gastrointestinal function of the broilers after DMG supplementation, as evidenced by the improved nutrient digestibility, the reduced gross lesion scores and the lower values in intestinal pH and viscosity.