The aim of this research is to process the OPEFB to become fiber with various sizes which will be used as a filler of polymer matrix recycled acrylonitrile butadiene styrene (ABS). Molecular analysis and mechanical test have been done to understand the influence of fiber size toward material capability to receive outer deformation. Single screw extruder formed a biocomposites granular continued with injection moulding to shaped test pieces. Maleic anhydride was added as coupling agent between filler and matrix. Filler concentration were 10 and 20% in fiber size respectively with constant additif. Two kind of fiber glass (10%) were used as comparator. In order to analyze the results of the mechanical test Fisher least significant difference (LSD) in ANOVA method was performed (-with α= 0, 05-).