This paper builds a time-of-use (TOU) tariff model based on load factor for industrial and commercial users of large and medium scale according to the coordination between TOU tariff and load factor tariff. First, this paper analyzes the system operation characteristics and power supply cost, and under the assumed condition that the programming and operation of power system is optimal to make the marginal capacity cost model and marginal electricity cost model for system and load factor grading users. Then considering of the price difference of each voltage grade, this paper establishes the load factor TOU tariff model applying the marginal cost pricing and two-part tariff theory. The pricing model synthetically reflects the generation, transmission and distribution cost and their time-variant characteristic, which makes the pricing model more efficiently and fairly. Finally, the case verifies the rationality of the model.