ABSTRACT The usage of food by‐products and waste has become a significant concern to stakeholders in food processing due to the environmental impact and the waste of resources. The soybean's by‐product is okara, which is rich in protein and other nutrients. The effects of substituting okara powder into whole wheat flour on nutritional qualities, antioxidant activities, and functional and pasting properties of the composite flour were determined using standard procedures. The results showed an increase in the composite flour's nutritional, functional, and antioxidant activities compared to the control (Whole‐wheat flour). The amino acid profile of the composite flour was higher in terms of all essential amino acids than that of the control samples. Okara powder added to whole wheat flour reduced the pasting properties except for the pasting temperature and peak time. The biscuits made with 10%, 20%, and 30% okara powder with whole wheat flour have similar scores to biscuits made with whole wheat flour alone. Compositing okara powder with whole wheat flour may be a raw material for healthy snacks in the confectionery industry.