Provided is a medical device having excellent wettability and lubricity and reducing a risk of bacterial proliferation. The medical device of the present invention is a medical device in which a layer made of an acidic polymer and a basic polymer is formed on at least a part of a surface of a water-containing base material. At least one kind of an acidic polymer and a basic polymer forming the acidic polymer or the basic polymer is a polymer having a hydroxy group, and the polymer having a hydroxy group is obtained by radical copolymerization of an acidic monomer or a basic monomer and a monomer having a hydroxy group.