To provide a copolymer latex for paper coating and a composition for paper coating with which coated paper having high coating operability and exhibiting high pick strength in printing may be obtained.

A copolymer latex for paper coating comprises: 40 to 90 wt.% of a copolymer latex (A) and 10 to 60 wt.% of a copolymer latex (B). The copolymer latex (A) is obtained through emulsion polymerization of 45 to 70 wt.% of an aliphatic conjugated diene-based monomer, 1 to 10 wt.% of an ethylenically unsaturated carboxylic acid-based monomer and 20 to 54 wt.% of an ethylenically unsaturated monomer copolymerizable with these monomers. The copolymer latex (B) is obtained through emulsion polymerization of 20 wt.% or more and less than 45 wt.% of an aliphatic conjugated diene-based monomer, 1 to 15 wt.% of an ethylenically unsaturated carboxylic acid-based monomer and 40 to 79 wt.% of an ethylenically unsaturated monomer copolymerizable with these monomers.