A porous film wherein the electrolytic solution absorption height in the lengthwise and/or widthwise direction of the film is 10 to 60mm as determined 30 minutes after the initiation of absorption of the electrolytic solution, and the breaking strength in the lengthwise direction is 65MPa or more. The porous film exhibits high absorptivity for an electrolytic solution. When used as a separator, the porous film ensures excellent cell characteristics and excellent cell fabrication.
