The system of shore-to-ship power supply for vessels in port has outstanding social benefits for the social environment,ship-owner,port.But it cannot cover the large-scale investments for the investor.Based on the investment of shore-to-ship power supply,the article uses financial internal rate of return method and break-even analysis to calculate the charge standard,furthermore,analyses the investment mode of shore-to-ship power supply for vessel in port to explain the feasibility of the system reformation of on-shore power for vessels in port at the present stage.