A porous film is here disclosed which is obtainable by stretching a film in at least uniaxial direction, said film being formed from a resin composition containing 25 to 70 parts by weight of a polyolefin resin and 75 to 30 parts by weight of an inorganic filler; said resin composition further containing 0.5 to 10 parts by weight of dehydrated castor oil (a) and 0.01 to 5 parts by weight of hardened castor oil (b) based on the total 100 parts by weight of the polyolefin resin and the inorganic filler; and the amount of the component (a) being 20 to 95% by weight based on the total amount of the components (a) and (b). In this porous film, softness and feeling like cloth, moisture vapor transmission, uniformity of the film thickness and the like are equal to their conventional levels. Furthermore, the adhesive strength of a securing tape does not deteriorate because the third components (a) and (b) do not float on the surface of the porous film. Therefore, it can be suitably used as materials of articles such as disposable diapers fixable and attachable by securing tapes.