PURPOSE: To obtain a layered plasma polymer membrane keeping high selectivity even when repeatedly bending it or used under pressurizing/pressure-reducing conditions by laminating permeable layers and selective layers on a supporting film and plasma-polymerizing them.

CONSTITUTION: The permeable layers having twice or higher permeability than the respective adjacent selective layers and the selective layers having higher selectivity than the adjacent permeable layers by at least 50% are alternately laminated on the supporting film and then polymerized using plasma to obtain the objective layered selective/permeable membrane having at least 2n layers (where (n) is ≥2 and the number of the selective layers) of ≤5 μ thickness.