The adhesion between vegetable fibres and the polymeric matrix remains one of the technological bolts of the development of composites. Indeed cellulose, the principal constituent of vegetable fibres, is not generally compatible with thermoplastic matrices. Many studies thus focus on the improvement of these properties, in particular by the means of physical or chemical treatments of fibres. The objective of this work was the chemical modification of cellulose by epoxidized soybean oil to improve compatibility between the cellulose and the matrix. The effect on the physico-mechanical properties of the PVC/cellulose composites containing 10 to 30% treated cellulose was studied. The resultant composites were characterized various tests (mechanical, thermal and morphological).