To provide a resin emulsion for sealers having excellent freeze damage resistance, water permeation resistance of coating film and coating film strength.

The resin emulsion for sealers comprises an inner layer constituted of a polymer obtained by emulsion polymerization of a monomer component containing 85-100 wt.% of an aromatic monomer and 0-15 wt.% of an ethylenic unsaturated monomer, has a weight ratio (polymer constituting the inner layer/a polymer constituting an outer layer) of the polymer constituting the inner layer to the polymer constituting the outer layer of 10/90-60/40, a total content of the polymer constituting the inner layer in the emulsion particles and the polymer constituting the outer layer of 40-100 wt.%, a content of styrene in a total monomer components of 5-40 wt.%, a content of monomers except styrene of 60-95 wt.%, a content of a carboxy group-containing monomer in the monomer component used in the outer layer of 1-10 wt.% and an amount of monomers except the carboxy group-containing monomer of 90-99 wt.% and a glass transition temperature of the emulsion particles of -70 to 10°C.