The shear strength of unsaturated completely decomposed granite (CDG) soil was studied by performing a series of unsaturated direct shear tests under different combinations of net normal stress and matric suction conditions. The axis-translation technique is applied to control matric suction. A series of typical soil water characteristic curves (SWCC) of CDG soil under different net normal stresses were obtained considering consolidation process by monitoring the vertical displacement throughout the tests. Experimental results show that both unsaturated shear strength and SWCC are affected by the soil stress states. Shear dilation behavior is observed significantly obvious at higher suction and lower net normal stress state, and the shear strength of unsaturated CDG soil increases with matric suction and net normal stress.