The main target of this work is to throw light on the replacement effect of wheat bran (WB), oat flour (OF) and Unripe banana flour (UB) at different levels instead of the physical, chemical and organoleptic properties of hard sweet biscuit. The obtained results showed gradual decrease in biscuit diameter (cm) by  the increasing levels of either OF or UBF, but it was gradually increased with WB. In contrary, thickness (cm) and biscuit weight (gm) were progressively increased by the increasing levels of all tested samples. In addition, when the wheat flour replaces by either WB or OF, the biscuits were characterized by higher protein, ash and fiber contents more than the control sample, with lower total carbohydrates and caloric values. On the other side, the biscuits produced with UBF are characterized by lower contents of both ether extract and caloric value, and the higher content of both ash and fiber contents than the control sample. Moreover, no significant differences were observed in all organoleptic properties of tested biscuits with either WB or UBF up to 20% or with OF up to 75%. In conclusion, the replacement of wheat flour by WB, OF and UBF in biscuit caused increase in protein, except UBF, crude fiber and ash contents, in addition decrease in carbohydrates and caloric value in biscuit without any affecting on sensorial and physical properties.