Herein, the preparation of polyurethane nanofibrous microfiltration membranes, with electrospinning and then dip-coating methods was reported. The study of process parameters (i.e. needle-free electrospinning and dip-coating condition) on the membrane properties was also conducted. The different pore sizes of the prepared MF membranes (e.g. 0.23, 0.33, and 0.47 mu m) is orchestrated through the adjustment of various electrospinning and dip-coating parameters. The capability of these membranes to simultaneously eliminate the sources of water pollution, i.e. micro-particles and bacteria, has been demonstrated. Specifically, the prepared membranes could thoroughly reject theE. coliBL21 (DE3) bacteria (similar to 97-99%) as well as micro-particles through size extrusion mechanism (similar to 95-99%), while they retained a high permeation flux (similar to 65,400, similar to 40,000 and similar to 25,700 (L/m(2) h bar) for 0.46, 0.33, and 0.25 mu m pore size, respectively). In addition, a comparison between nanofibrous MF membranes and their commercial counterparts from both utility and effectiveness standpoint was conducted and the obtained result indicated the supreme performance of these membranes in comparison with the commercial membranes of the same mean pore size, also with almost double or triple higher flux.