The quality of municipal solid waste affects the performance of incinerator waste-to-energy plants. This study aimed to identify and analyze the pre-treatment process for municipal solid waste in order to improve the quality of waste which will be used as feedstock to a waste-to-energy plant using pre-treatment equipment in terms of process rate, mass balance, and waste quality before and after the pre-treatment. The municipal solid waste came from resident housing in DKI Jakarta and the pre-treatment facilities used consisted of a feeder conveyor, trommel screen, and sorting conveyor, as well as excavators. The research was done quantitatively. The results of this study show that the pre-treatment process assisted by 17 workers in one work shift (7 hours) can handle 39.06 tons of waste. The waste consisted of 10.5% bulky waste, 27.6% materials smaller than 5 cm, 1.5% recyclable materials (metal, glass, and plastic), and 59.5% combustible materials. The combustible material was relatively free from bulky material, inert material, and hazardous material. Its calorific value increased from 6.61 MJ/kg to 8.80 MJ/kg. It is concluded that waste after pre-treated had good quality as a feedstock of incinerator waste-to-energy.