---

Abstract-Due to growing demand of the electric energy, the need to transmission expansion planning is inevitable. In this paper at first the effective criteria in transmission Expansion Planning (TEP) are determined and a novel approach for TEP is proposed. In this approach Analytical Hierarchy Process (AHP) and entropy technique are utilized for TEP. The entropy is one of the techniques that uses for weight assessment in decision making in Multi Criteria Decision Making (MCDM) model. For this purpose, five criteria are introduced and then by utilization of the Entropy-AHP (EAHP), the optimization of TEP problem is implemented. In the first stage, the Local Marginal Price (LMP) of each bus is calculated by Optimal Power Flow (OPF) execution. In the next stage, base on the criteria that will describe, the candidate lines are determined. Finally, the EAHP is used to assign a value to each criterion and by using these values the optimal line among the candidate lines is determined. The IEEE 14 bus network is used to simulate and evaluate the effectiveness of the proposed method..