A polyester for a toner, obtainable by polycondensing an alcohol component and a carboxylic acid component containing a fumaric acid-modified rosin; and a toner containing the polyester for a toner. The polyester for a toner of the present invention is usable as a resin binder for a toner usable in, for example, developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.