A toner for developing electrostatic images, includes toner particles and 10-500 isolated low-molecular weight wax particles per 10,000 toner particles. The toner has a melt index as measured at 125.degree. C. under a load of 98 N of at least 10. The toner particles comprise at least a binder resin, a colorant and the low-molecular weight wax. The low-molecular weight wax comprises a compound represented by the formula of: R--Y, wherein R denotes a hydrocarbon group, and Y denotes a hydroxyl group, carboxyl group, alkyl ether group or alkyl ester group. The low-molecular weight wax has a thermal property providing a DSC curve as measured by a differential scanning calorimeter exhibiting: (i) a maximum heat-absorption peak having a peak temperature in a temperature range of 70.degree.-130.degree. C.; (ii) a heat-absorption peak including the maximum heat-absorption peak showing an onset temperature of at least 50.degree. C., and (iii) a maximum heat-evolution peak in a range of .+-.15.degree. C. from the peak temperature of the maximum hat-absorption peak. The toner shows a good fixability while retaining a good productivity through the melt-kneading-pulverization process.