The invention discloses a garbage incineration furnace low-energy-level working medium and coal fired boiler coupled high-energy-level utilization system. With garbage treatment as purpose, a garbageincineration furnace uses incineration heat in an afterheat boiler with a superheater inside, and is lower in power generation efficiency. The system comprises a high-pressure heater (1); a way of a water feeding pipeline (7) with a water feeding pump (2) of the high-pressure heater is connected with an afterheat furnace heated surface of a garbage incineration furnace (3); an outlet water pipe (8) of the garbage incineration furnace is connected with a tail coal economizer (5) of a coal fired boiler (4) after gathering with the other way of the water feeding pipeline of the high-pressure heater; and stop valves (6) are arranged on the water feeding pipeline connected with the afterheat furnace heated surface and the outlet water pipe of the garbage incineration furnace. The invention is applied to the garbage incineration furnace low-energy-level working medium and coal fired boiler coupled high-energy-level utilization system.