Oil palm fiber empty fruit bunch (EFB) was chemically treated with benzyl chloride (bz-efb) and ethylene oxide (E-efb) at different reaction temperatures (100 and 110 degreesC for bz-efb; 55, 85, and 92 degreesC for E-efb). The SEM micrographs of bz-efb and E-efb samples showed tremendous changes in morphological structure such as plastic properties as the reaction temperature was increased. The crystallinity (by XRD) and T-g of the reacted fibers were found to decrease as the reaction temperature increased. The FT-IR of the reacted samples show that the chemical reactions have taken place between cellulose hydroxyl groups and bz-efb and E-efb, respectively.