Cotton gin trash (CGT), a potential lignocellulose resource was combined with poly(vinyl alcohol) (PVA) to produce the biodegradable composite plastic film. A 50:50 CGT/PVA ratio was maintained using coarse and fine CGT powder particles and the effect of particle size on the morphology, crystallinity, tensile strength, optical transmittance, thermal stability and biodegradability was investigated. Scanning electron microscope (SEM) image showed uniform distribution of CGT in PVA matrix particularly of the fine powders (similar to 5.7 mu m). The incorporation of CGT in PVA enhanced the tensile strength, biodegradability, thermal stability and induced complete UV protection. Overall, while the flexibility of the composite film decreased, the tensile strength increased 10% and 20%, respectively by the coarse and fine CGT powders when compared to the pure PVA film. Considering the fabrication cost as estimated in the study, the results point towards the immense potential of CGT as a low-cost reinforcement material for PVA to be successfully used in the production of biodegradable plastic material. (C) 2020 Elsevier B.V. All rights reserved.