A nanoemulsion emulsification composition, comprising the following components (A) to (D), wherein: the mass ratios of the components satisfy the following condition, A + B : C : D = 1 : 4 to 8 : 0.4 to 0.8 ； the component (A) is a copolymer comprising a constitutional unit (a1) represented by Formula (1) and a constitutional unit (a2) represented by Formula (2), the molar ratio of the constitutional units (a1):(a2) being 5:95 to 60:40, and the weight average molecular weight being 5,000 to 5,000,000； (wherein, R 1 represents a hydrogen atom or a methyl group) (wherein, R 2 represents a hydrogen atom or a methyl group, and R 3 represents a hydrocarbon group having 12 to 24 carbons)； the component (B) is a nonionic surfactant having an HLB value of 10 to 14； the component (C) is a polyhydric alcohol； and the component (D) is water.
