Two field experiments were conducted in 2015 and 2016 seasons at Kom Ombo, (latitude of 24°28'N, longitude of 32°57'E and altitude of 108 m), Aswan Governorate, Egypt. Each experiment contained nine treatments of intercropping groundnut (companion crop) with maize (main crop) on ridges at different plant densities of both crop i.e., P₁ = 100% main crop + 100% companion crop, P₂= 100% main crop + 75% companion crop, P₃= 100% main crop + 67% companion crop, P₄ = 100% main crop + 50% companion crop, P₅ =100% main crop + 33% companion crop P₆ =75% main crop + 100% companion crop, P₇ =67% main crop + 100% companion crop, P₈ =50% main crop + 100% companion crop, P₉ =33% main crop + 100% companion crop, beside pure stands of main crop and companion crop. Results indicated that maize and groundnut plants grown under intercropping showed significant variation in 100-grain weight, grain yield/plant, grain yield/fed., and crude protein for maize, as well as number of branches/plant, number of pods / plant, 100- seed weight, pods yield /fed., crude protein and oil percentage of groundnut during the two seasons. Grain yield/fed. of maize and pods yield/fed. of groundnut were significantly reduced by all intercropping systems. The least reduction was recorded at (P₂) ratio. The (P₂) ratio was the best for land utilization as indicated by land equivalent ratio and the most efficient intercropping ratio concerning relative crowding coefficient. The (P₁) ratio was more aggressive on maize. All intercropping ratios of groundnut with maize achieved higher economic return than pure maize and the most profitable ratio was (P₂).