Abstract: Provided is a toner for developing electrostatic images having excellent low temperature fixability and heat resistance storability. In order to achieve at least one of the aforementioned purposes, provided is a toner for developing electrostatic images containing a first resin which is a crystalline polyester resin consisting of a dicarboxylic acid unit and a dialcohol unit (weight average molecular weight is 5000 to 100000); a second resin (weight average molecular weight is 5000 to 60000) which is a polyester resin consisting of a crystalline segment (weight average molecular weight is 200 to 3000), which consists of a dicarboxylic acid unit and a dialcohol unit, and an amorphous segment, in which a specific carbon number relationship is present between each unit.