Composite flour is flour made from two foodstuffs, namely Tengger potatoes and Moringa leaves. Composite flour can be used as a substitute material for wheat flour for the manufacture of crackers products. Crackers are a type of biscuit that goes through a fermentation process. The study aimed to find out chemicals and physicals properties composite flour substitution crackers with a fermentation length of 0 hours, 1 hour, and 2 hours. This study using a Complete RandomIzed Design with 3 treatments and two repeats. The results of the analysis showed the old fermentation treatment of crackers dough significantly effect from its chemical and physical properties. Crackers with a 2hour fermentation period contain the highest protein content of 16.44%, the mostten water content of 0.916%, and the lowest free fatty acid content of 0.014%, and physical properties include the highest growth power of 28.237%, the lowest broken power of 0.006N/Cm² and the brownish index of 88.469%.