Cookies are classified as biscuits “soft dough”. There are many textural properties in cookies such as color, tenderness, and flavor but the most pronounced textural property is tenderness provided by the high-fat content (Zoulias et al,2000) ; Obeidat et al,2018). This study explained the effects of fat replacement with WPIs at different concentrations (0, 10, 20, 30, and 40%) on cookies regarding proximate analysis and sensory characteristics. The highest fat percentage was observed in Cookies (40%). The data revealed a significant increase in moisture content with increasing WPI in cookies. Moreover, the fat replacement WPI (1:1) reduced the fat contents of cookies and was directly proportional to the level of fat replacement. The samples subjected to WPI presented increased protein contents, which were directly proportional to the level of WPI added. There was no significant effect on cookie color at all WPI levels. Fat replacement with WPI had no significant effect on the softness or overall acceptability of cookies up to 20. In addition, WPI as a fat replacer had no significant effect on the flavor of cookies at any added level.