The present invention relates to a resin emulsion being produced by neutralizing a resin binder containing acid group with a basic compound in an aqueous medium wherein the resin binder containing acid group contains a polyester produced from a raw monomer composition containing a trivalent or higher-valent polyhydric alcohol in an amount of 1 to 15 mol %; a process for producing the resin emulsion; and a toner for electrophotography using the resin emulsion. In the resin emulsion of the present invention, a resin is readily emulsified therein even when using a crosslinked polyester as the resin, and the resin emulsion is substantially free from hydrolysis of the resin and can produce a toner having an excellent heat-resistant storage property.