[PROBLEMS] To produce a hyper-branched polymer having excellent resin strength, a good anti-blocking property and less environmental dependence. [MEANS FOR SOLVING PROBLEMS] Disclosed are: a hyper-branched polymer of an ester type, wherein number-average molecular weight is 1,000 to 60,000, weight-average molecular weight/number-average molecular weight is within a range of from 2 to 15, glass transition temperature is not lower than 30.degree. C. and hydroxyl value is 2 to 450 mg KOH/g; and a toner for electrophotography using the polymer. Preferably, disclosed are: the hyper-branched polymer of an ester type, wherein alicyclic or aromatic carboxylic acid where a molecular weight is not less than 100 has been made to react with a functional group of the core part of the hyper-branched structure of an ester type; and a toner for electrophotography using the polymer.