Porous hollow fiber membrane and method for manufacturing same

Provided is a porous hollow fiber membrane and a method for manufacturing same, the porous hollow fiber membrane being able to be used suitably in devices for processing various water-based fluids for use in applications such as water purification, drinking-water processing, and seawater clarification; having excellent fractionation characteristics and permeability with minimal decrease in performance over time; having excellent recovery in membrane separation characteristics by washing: and having excellent separation characteristics, filtration stability, and mechanical strength. The present invention is a porous hollow fiber membrane having a porous layer made of a thermoplastic resin in at least an outer surface and the vicinity thereof, the average pore diameter (Ad) at a depth of 1 [mu]m from the surface as seen in cross-section being no more than 0.6 of the average pore diameter (Bd) from a depth of 2 to 3 [mu]m, and a method for manufacturing said membrane. 本发明提供一种多孔质中空纤维膜及其制造方法，其可适用于净水处理、饮用水处理、海水除浊等各