The present invention provides a material for electrical insulating organic film, superior in electrical properties, thermal properties and low water absorption; an electrical insulating organic film made from the material; and a process for production of the film. That is, the present invention provides an electrical insulating organic film having fine pores, consisting of a layer of a polybenzoxazole resin represented by the following general formula (1): wherein n is an integer of 2 to 1,000; X is a tetravalent organic group; and Y is a bivalent organic group; a material for electrical insulating organic film obtained by mixing a polybenzoxazole precursor or a polybenzoxazole resin, with an oligomer; and a material for electrical insulating organic film, obtained by reacting at least one carboxylic acid terminal of a polybenzoxazole precursor with an amino group- or hydroxyl group-containing oligomer. The above electrical insulating organic film is produced by a process which comprises mixing a polybenzoxazole precursor or a polybenzoxazole resin with an oligomer, forming a film from the resulting mixture, and heating the film to give rise to thermal decomposition and gasification of the oligomer, to obtain a polybenzoxazole resin layer having fine pores; or by a process which comprises reacting at least one carboxylic acid terminal of a polybenzoxazole precursor with an amino group- or hydroxyl group-containing oligomer to synthesize a material for electrical insulating organic film, forming a film from the material, heating the film to give rise to ring closure of the polybenzoxazole precursor, further heating the resulting material to give rise to thermal decomposition and gasification of the oligomer group, to obtain a polybenzoxazole resin layer having fine pores.