In this research, the performances of pH value on shear strength behavior of granular soil have been studied. The shear strength of soil is an important term in most of the foundation engineering problems such as the bearing capacity of shallow foundation, slope stability of dam/embankment and lateral earth pressure on retaining walls. A series of direct shear test were conducted on two types of dry granular soils (taken from Rangpur and Rajshahi areas of Bangladesh) with different pH value (pH=0, pH=3.0, pH=5.0, pH=7.0 and pH=9.0). Hydrochloric acid (HCl) and ammonia (NH4) solution were used to monitor the pH of the solution for about thirty days. In all, 15 specimens of each type of soils were considered for direct shear test with dry condition at a constant density. The specimens were prepared by static compaction with different pH values solution (0, 3, 5, 7and 9) at same void ratio. Experiment result shows that the shear strength increase with increase of pH values of soil.