This research paper experimentally investigated the effect of wt.% and length of fiber on the water absorption behavior and tensile strength of chopped (6 and 12 mm) Grewia optiva/Basalt fiber reinforced hybrid polyester composites. The research work is carried out using five different compositions (0, 3, 6, 9, and 12 wt.%) of Basalt fiber prepared by hand layup technique, and samples are placed inside the distilled water for the duration of six months. The maximum wt.% of the fiber is 12 wt.% of composite, and weight gain by the composite is measured every month to carry out the research work. The water absorption, void fraction, and tensile strength of the composites are determined according to suitable ASTM standard.