Determining the shear strength properties of the soil is a vital step in investigation its stress-strain behavior. Moreover, suction plays a vital role in the shear strength of the unsaturated soil. This paper investigates the influence of the fiber glass on the shear strength parameters of (c-ɸ) soil with different ratios. To achieve this purpose, the samples of (c- ɸ) soil from El-Fardos gardens housing compound, Benha city, Egypt, were prepared at their maximum dry densities with corresponding optimum moisture content. Direct shear box test of 60 x 60 mm under a relentless rate of 1 mm/min was employed with the proposed range of ASTM D 3080. Different fiber glass ratios of 0.1, 0.50 and 1.00 % of soil sample weight were used. The results confirmed that the peak shear strength parameters increased with increasing the fiber ratio