Herein, the microcrystalline cellulose (MCC) was obtained from jut ber by ammonium persulfate (APS) oxidation process and thus polyvinyl alcohol (PVA) composite lms were prepared by the reinforcement of MCC in a solution casting method. The surface chemistry, thermal properties and surface morphology of MCC and PVA-MCC composite lms were studied by FT-IR spectroscopy, thermogravimetric analyzer and scanning electron microscopy. The SEM images con rmed the rod like MCC with average particle diameter 4.6 µm and length in 48.4 µm. The FT-IR spectroscopy revealed the complete removal of lignin and hemicellulose from jute ber. A peak at 1730 cm− 1 was introduced in MCC due to oxidation with APS. The absorption peak of–OH groups in PVA-MCC composite lms were shifted, somewhat disappeared and weakened due to the intra and inter molecular hydrogen bonding of MCC and OH groups in PVA. Thermogravimetric analysis expressed the thermal behavior of MCC and PVA-MCC composite lms. Initially the thermal stability of PVA-MCC composite lms was lower than the pristine MCC but at higher temperature (> 300℃) it showed better stability indicating the applicability of the composite at higher temperature.