During the processing of fruits, large quantities of wastes are generated, these by-products contain large amounts of oil, starch and protein that can be exploited due to their good nutritional, technological, and functional properties. However, due to the presence of several antinutritional factors, such as polyphenolic compounds, phytic acid, cyanogenic glycoside and oxalates, the use of fruit wastes in human food is limited. The present investigation was aimed to study the effect of soaking and heating on antinutritional factors. It also examines the effect of substituting defatted apricot, peach, and mango seed kernel flours for wheat flour in various ratios (5, 10, and 15%) on the chemical composition, physical features, and sensory properties evaluation of biscuits. The results revealed a significant effect of soaking and heating on the antinutrients, detoxification led to a significant (p≤0.05) decrease in antinutritional factors with ratios 43.63-52.73% total phenols, 78.17-86.16% tannins, 45.92-54.34% phytic acid and 40.42-44.70% oxalates, along with the complete removal (100%) of hydrocyanic acid (HCN). Wheat biscuit contained 3.20% moisture, 6.31% protein, 15.46% fat, 0.64% crude fiber, 1.25% ash and 76.33% carbohydrate. Highly acceptable biscuits could be obtained by incorporating 5% of defatted apricot, peach and mango kernel flours in the wheat biscuits formulation. As a by-product, apricot, peach and mango kernels offer an exciting potential as a food ingredient permitting to enrich biscuits and enlarge the food base for consumers.