A nanofibrous microfiltration membrane with high flux, low pressure drop, and high retention capacity was fabricated by pore filling of copolyetherester nanofibers (low-melting-point polyester; melting point of 110celcius) into a poly(ethylene terephthalate) nonwoven scaffold. Short low-melting-point polyester nanofibers were anchored on the surface of the poly(ethylene terephthalate) fibers by heat treatment to form a crosslinked nanostructured mesh with very high porosity and high specific surface area. The pore size and distribution of the membranes can be adjusted by varying the loading amount of nanofibers. The resulting membrane not only possessed good interception ability for 5, 3, and 1.3 mu m polystyrene microspheres but also exhibited desirable water permeability. In the circulating filtration test, with the accumulation of membrane fouling in the filtration, the membrane was also effective in retaining particulate matter while improving the antipollution ability. These properties are desirable for the effective removal of pollutants on the membrane and restoration of the membrane flux.