In this present research, biscuit was prepared with the addition of guava seeds powder at the ratio of 5, 10 and 15 %. Chemical, rheological, sensorial and microbial properties were evaluated for different biscuit samples. Addition of guava seeds improved the functional of biscuits which prepared from it. Incorporation of guava seeds powder in biscuit dough revealed an increase in dough stability, Elasticity, P.N and energy (cm²) values and a decrease in water absorption and degree of softening values. Result of sensory evaluation of biscuits samples which prepared from guava seeds powder showed non-significant differences at (P≤0.05) between all samples of biscuits formulas. Addition guava seeds powder to biscuits samples caused an increase in total essential amino acids from 50.1 to 57.0, 64.7 and73.9 mg/g while total amino acids represented 65.3, 68.4, 73.4 and 80.5 mg/g in biscuits samples supplemented with 0, 5, 10, 15 % guava seeds powder, respectively. Supplementation of guava seeds powder with the ratio of 5, 10 and 15 % to biscuits formulas reduced microbial counts. It concluded that the additions of guava seeds powder to wheat flour based biscuit improve its nutritional and rheological functions properties.