In this study, to fabricate a pH resistant membrane with antifouling properties, a Tris-grafted polyamine thin film composite (TFC) membrane has been synthesized. The prepared membranes were characterized by ATR-FTIR, FESEM, AFM, and water contact angle analysis. The reaction of Tris and residual chloride groups was conducted on the surface of the TFC to enhance the hydrophilicity and antifouling properties of the membrane. The effect of reaction temperature and reaction time on the hydrophilicity, membrane flux, rejection, and antifouling properties was evaluated. The modified membrane exhibited a flux of 48.17 L m⁻² h⁻¹ and FRR of 83%. Compared to the unmodified membrane with a flux of 26.23 L m⁻² h⁻¹ and FRR of 27.67%, surface modification by Tris-grafting had a significant impact on the polyamine TFC membrane hydrophilicity and antifouling properties. The pH resistance test shows that the Tris-grafted polyamine membrane can operate up to one month in harsh chemical conditions without a significant change in membrane performance.