Object: To provide a method for manufacturing a polymer, which is a method for forming a polymer having a homogeneous copolymer composition and a narrow molecular weight distribution.
Resolution Means: A method for manufacturing a polymer using a microreactor including a flow path capable of mixing a plurality of liquids to perform radical polymerization of a monomer component containing two or more types of monomers in the presence of a polymerization initiator; wherein the microreactor includes a first inlet port configured to feed the monomer component and an additional inlet port located downstream of the first inlet port; and the method includes feeding the monomer component through the first inlet port and the additional inlet port.