To prepare stable and relatively low-viscosity emulsions such as vinyl acetate-based emulsions, (meth)acrylate-based emulsions and styrene-butadiene- based emulsions.

An emulsion comprises (A) a polyvinyl alcohol-based polymer having mercapto groups with an average saponification degree (X) of 85 mol.% or more and (B) a polyvinyl alcohol-based polymer with an average saponification degree (Y) of 85 mol.% or less, wherein X minus Y is 5 mol.% or more and the weight ratio of solid contents of A/B is 100/0.1-100/50.