Disclosed is a method for producing a medical instrument having a lubricating layer (a coating layer) exhibiting excellent durability (particularly, sliding durability). The method for producing a medical instrument is a method for producing a medical instrument having a base layer, and a lubricating layer that is carried on at least a part of the base layer. The method for producing a medical instrument also includes applying, to the base layer, a solution containing a block copolymer having a structural unit (A) derived from a reactive monomer having an epoxy group and a structural unit (B) derived from a hydrophilic monomer, an alkylammonium salt having 8 to 24 carbon atoms, and a solvent； and washing off the solution applied to the base layer.
