The invention discloses a system and a method of charging step tariff applied to a power user end. Power utilization time and an electric meter code during the power utilization time of a power user are acquired; account cancellation information and a meter reading frequency of the user are recorded, the actual power utilization month number is calculated according to the account cancellation information and the meter reading frequency, and a step electric quantity is further calculated; an annual step electric quantity and a step electric price of the user are determined; the cumulative power utilization quantity last month, power utilization quantity in the current month of the user and the annual step electric quantity by a step electric quantity charging unit are determined, the falling step for the electric quantity which needs to be charged to the user is determined; and according to the step for the electric quantity which needs to be charged to the user, the electric price of the step electric quantity charging unit is called, and the current electric fee in the current month by the user is calculated and displayed. By only acquiring the initial code and the stop code of the electric meter, which step period the current user is in can be known, the electric price of each step can be clearly known, how much electric quantity can be used for each step can be known, and the power utilization condition of the user can be mastered by the user.