A successful and novel formulation of cake production with watermelon rinds and sharlyn melon peel powders were developed. Watermelon rinds and sharlyn melon peels are good sources of phenolic compounds and dietary fiber. Cake batter formulated with partial substitution of flour or fat with 5% watermelon rind or sharlyn melon peel powders had bioactive components as compared to cake prepared with 100% wheat flour. Watermelon rind and sharlyn melon peel were good in antioxidant activity to increase shelf-life of cake. Substitution of wheat flour at 5% is recommended to produce an acceptable cake. Overall, it could be recommended that the technology of using watermelon rind and sharlyn melon peel powders should be encouraged among food industries to make economic use of local raw materials to incorporate into cake and provide cake with more functional components and more effective antioxidant activity.