To obtain a deinking agent excellent in cohesion of finely divided carbon or whiteness degree by using a compound having a hydrophobic group comprising a specific hydrocarbon group and a hydrophilic group prepared by randomly copolymerizing an ethylene oxide/propylene oxide as an essential component.

This deinking agent is prepared by using a compound, represented by the formula R1O-(AO)n-H [R1 is an 18-36C hydrocarbon, preferably an alkyl; AO is a polyoxyalkylene chain composed of the random copolymerization of ethylene oxide/propylene oxide at (5/1) to (1/5) molar ratio; (n) is 1-1,000] and having 500-50,000 molecular weight as an essential component.