The present invention relates to a organopolysiloxane graft polymer including an organopolysiloxane segment as a main chain thereof and an unsaturated monomer-derived polymer segment as a side chain thereof, in which the unsaturated monomer-derived polymer segment contains a repeating unit derived from N,N-dimethyl acrylamide in an amount of not less than 50% by mass and not more than 100% by mass, and a content of the organopolysiloxane segment in the organopolysiloxane graft polymer is not less than 10% by mass and not more than 70% by mass.
