Incineration is indispensable for burnable refuse disposal, and power generation by waste is environment-friendly and power system-friendly with synchronous generators. Optimal operation planning of incinerator plant is a key point to make much of this merit. We have studied on actual operational data of incinerator plant in Tokyo Metropolitan Area (TMA) applying GA. The subjects of these studies include improvement of GA program, rechecking of the basic data, etc. This paper proposes improved optimal method considering actual constraints of refuse disposal administration. As the result of improved GA program, it has become possible to increase generation energy more rationally.