To provide a method for manufacture of a porous film having a high strength, a high specific surface area and a high pore volume are provided, and also excellent in an ion permeability and high speed charging and discharging properties.

The manufacturing method comprises the steps of melting and kneading a resin composition containing a polyolefin resin and a solvent, molding the obtained melted and kneaded product in a sheet shape, rolling the obtained sheet-shaped product by a heating belt press and a cooling belt press and thereafter, drawn and subjecting the rolled product to stretching and desolvating treatments. In this case rolling treatment is executed at a temperature ≥ a melting point of polyolefin resin -30°C and ≤ the melting point -10°C, and the rolling treatment by the cooling belt press is executed at ≤40°C.