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Several different types of soils in nature are more commonly found in a state of unsaturated condition, particularly in arid and semi-arid regions. Also, expansive soils, collapsible soils, residual soils and compacted soils are conventionally categorized as problematic soils. These problematic soils are frequently in a state of unsaturated condition. The influence of suction is generally ignored in conventional geotechnical engineering which adopts the conservative assumption that the soils are in a state of saturated condition. The matric suction is closely related to shear properties of unsaturated soils. The shear strength of unsaturated soils was formulated in terms of two independent stress variables (i.e. net normal stress and matric suction) (Fredlund et al. (1978)). The direct shear apparatus was developed for pressure membrane technique instead of pressure plate technique. This study presents shear properties under constant volume direct shearing for an unsaturated silty soil having a low matric suction.