Under distribution businesses orderly opening, the market behavior of Distributed Generation (DG) operators further increase the uncontrollability of their output. Distribution network operators need to use electricity pricing and other means to implement a certain degree of intervention and scheduling control on DG output to reduce the uncontrollability caused by the access of distributed power. This paper proposes a Locational Marginal Price (LMP) pricing method in distribution networks based on gas emission reduction allocation of DG using market cooperative game theory. Based on the priority of gas emission reduction and distribution network operators' benefit, the proposed pricing policy requires decision maker to simply apply its best response strategy to the LMP calculating, so as to carry out price compensation for the DG units participating in energy saving and emission reduction. The example result shows that the method can determine the price of DG nodes based on the completion schedule of emission reduction task. And the performance of this method is superior to the traditional method in the aspect of promoting energy conservation and emission reduction. With the tightening of energy conservation and emission reduction constraints in the future, the proposed method has high reference value and practical significance for the formulation of LMP and the efficient and safe operation of distribution system. This work is supported by Beijing Social Science Foundation (No. 15JDJGA089).