Polyamide porous membrane and preparation method thereof

The purpose of the present invention is to provide a polyamide porous membrane having improved liquid permeability. A polyamide porous film in which a dense layer is formed on at least one surface, and in which stripe-shaped recesses extending in one direction are formed on the surface of the dense layer, the orientation angle of the stripe-shaped recesses in a predetermined orientation analysis is 0-5.0 DEG or 175.0-180.0 DEG, and the orientation strength is 1.5-2.0. 本发明的目的在于提供一种透液性能提高的聚酰胺多孔膜。一种聚酰胺多孔膜，其在至少一面上形成有致密层，在所述致密层的表面具有沿一个方向延伸的条纹状凹部，规定的取向分析中的所述条纹状凹部的取向角度为0～5.0°或175.0～180.0°，取向强度为1.5～2.0。