Maize supplies poultry with a major part of their energy requirements, particularly in Ghana and some other parts of the world. However, most feed producers, especially in Ghana, do not examine feed particle size as a quality indicator in assessing feed preparations. Particle size of ingredients is critical in achieving optimum utilization by animals in as much as it is, in the overall process of handling and mixing (formulation) of ingredients to manufacture formulated feeds. The manner in which ingredients are ground and the coarseness of that grind has a direct impact on the physiology of birds. The effect of feed particle size was investigated in a five-week study using 120 mixed-sex four week-old Cobb-500 broiler chickens. This study aimed, therefore to determine the effect of variations of ground maize (as a major ingredient) in most complete feeds on broiler performance and subsequently suggest the best feed particle size to be used by farmers for broiler feed formulation.