This paper mainly analyzes the theory of light-rail. A few optimal fare-pricing models is established based on different objects. The authors combine the benefits of Society, Orbit company and the passengers to establish an AHP model for assessing the fare-pricing models. Finally, they establish an optimal fare-pricing scheme with light-rail. This model is applied to light-rail line 2 in Chongqing. A scale ticket price scheme of this object is given.