The invention relates to a steam reheating system for improving the energy utilization efficiency by improving the steam parameters of the garbage incinerator. The system involves the main componentsof a waste heat boiler, a steam reheater, a steam-water separator, a steam turbine high-pressure cylinder, a steam turbine low-pressure cylinder, a steam condenser, a deaerator, a water feeding pump and the like; and boiler main steam enters the steam-water separator after the steam turbine high-pressure cylinder does work, separated saturated water returns to a steam drum, saturated steam entersthe steam reheater and exchanges heat with saturated steam from the steam drum, and reheated superheated steam is introduced into the steam turbine low-pressure cylinder to do work. The system not only improves the energy utilization efficiency of the garbage incinerator, but also avoids the pipeline corrosion of steam reheating, and improves the equipment stability and the economic benefit of agarbage incineration plant.