Résumé : In this work, novel nanofiltration membranes with outstanding performance and antifouling properties were fabricated by incorporating composite graphene oxide/chitosan (GOC) nanoplates into the membrane structure. GOC composite nanoplates were prepared by surface modification of GO with chitosan. The GOC nanoplates were then introduced as additives in a polymeric phase in different concentrations (up to 1%) in view of membrane synthesis. these membranes were thoroughly characterized and assessed for their Na2SO4 and CrSO4 rejection and water flux. Furthermore, the antifouling performance of GO and GOC filled membranes in high concentration (1wt%) was investigated. Modified membranes with addition of GOCs showed a higher hydrophilicity, pure water flux and rejection, and a smoother surface compared to a bare PES and a GO incorporated membrane. SEM surface images indicated a more uniformed distribution of GOCs at a high loading rate (1wt%) compared to GO. Due to the uniform dispersion of GOCs, a better antifouling performance was observed than for GO filled membranes. The results indicate that surface modification of GO with chitosan can enhance the membrane performance and properties, due to availability of sites with higher activity.