Provided is a method for producing a reversible addition-fragmentation chain transfer polymerization polymer, which includes continuously rotating a reaction container accommodating a mixed solution which contains a monomer and a reversible addition-fragmentation chain transfer agent around a rotation axis inclined with respect to a vertical direction using a rotating photopolymerization reactor, while stirring a liquid pool of the mixed solution, to spread a mixed solution emerging from the liquid pool in a form of a film on an interior wall of the reaction container, and irradiating the mixed solution spread in the form of a film with light from a light source disposed outside the reaction container.