To prepare the hollow fiber nanofiltration composite membranes, the poly(vinylidene fluoride) (PVDF) membrane was hydrophilized with K₂Cr₂OH and KMnO₄ aqueous solutions. And then the composite membrane was synthesized on that membrane surfaces using interfacial polymerization with piperazine (PIP) and trimesoyl chloride (TMC). The resulting membranes were characterized in terms of the rejection and flux for NaCl, CaSO₄, MgCl₂ 100 ppm solution and 300ppm of NaCl and CaSO₄ mixed solution by varying the coating time, drying time, and the concentration of the coating materials. As a result, the higher rejections were shown for K₂Cr₂OH solutionas a hydrophilization material, and the flux was enhanced while the rejection reduced as the hydrophilization time is longer. Also, the rejection increased and the flux reduced as the concentrations of triethyl amine (TEA) and sodium lauryl sulfate (SLS) were higher. Typically, the rejection 50% and flux 40 LMH for NaCl 100 ppm solution, and the rejection 55% and flux 48 LMH for CaSO₄ 100 ppm solution were obtained for the PVDF hollow fiber composite membrane prepared with the conditions of PIP 2 wt% (Triethyl amine(TEA) 7 wt%, SLS 20 wt% mixed solution against PIP concentration) and TMC 0.1 wt%.