The invention relates to a method for preparing membrane, the corresponding membrane and filtering element. The method consists of: providing porous substrate with pore space; applying pre-filled solution, until the pore space of the porous substrate is occupied by a small part of pre-filled solution. The method also relates to the membrane prepared in accordance of the exploit example. The filtering element related to the method consists of: core tube; and the membrane prepared in accordance of the exploit example. The membrane is wound around the core tube.