Composites from biopolymer and biofiber becoming the value added materials from environment point of view. These materials have the potential to be the attractive alternative to the synthetic fiber composites considering both the cost and quality. In the present investigation composite specimens are prepared from biodegradable polymer matrix i.e. polyhydroxybutyrate-valerate (PHBV) and biofiber (kenaf) using injection molding technique. PHBV is the biodegradable biopolymer used as packaging materials. The objectives of the present work is to investigate the suitability of kenaf and bamboo fibers as reinforcing filler in PHBV composites, to study the effect of fiber content and effect of surface treatment (alkali treatment) of fibers on the mechanical properties and biodegradability of composites. Tensile properties of composites increased due to fiber loading and decreased due to alkali treatment (mercerization) of kenaf fiber. Impact strength of neat PHBV polymer was much higher than the composites. Impact strength of mercerized kenaf composites were higher than untreated fiber composites and increased with increase in fiber content. The tensile fractured surface morphologies of composite specimens were studied through SEM analysis. Change in mechanical properties, surface morphology and negligible degradation within ten weeks (70 days) of natural soil burial were observed from the investigation.