A novel thin film composite (TFC) nanofiltration (NF) membrane was prepared by introducing the capsaicin derivative AMTHBA into polyamide (PA) layer by bidirectional interfacial polymerization. Ultrathin, smooth and defect-free PA layers can be prepared by bidirectional interface polymerization. Meanwhile, the surface properties of NF membranes were precisely regulated by adjusting the concentration of AMTHBA in an aqueous solution. As a result, the AMTHBA-PA_R/PA_F/PS membrane displayed superior permeance owing to its hydrophilic and negatively charged surface. The optimized NF membrane exhibited an ultrahigh permeance of 128.95 L m⁻² h⁻¹ (almost two-fold higher permeance than that of the nanofiltration membrane prepared by traditional interfacial polymerization), together with a steady efficiency above 98.43% for rejection of Na₂SO₄. In addition, the AMTHBA-PA_R/PA_F/PS membrane exhibited excellent antifouling performance and therefore has broad application prospects in the field of water treatment.