There are problems in the evaluation of the operational status of overhead lines. Thus a comprehensive evaluation method based on a health index is proposed. The method combines the operational characteristics of overhead lines. It involves comprehensive consideration of the line itself and the external factors such as weather and environment. The method systematically considers the key factors and their influencing coefficients on the health status of the line. Taking into account the importance of different influencing factors and adopting a combination of qualitative and quantitative methods, a calculation method for the line health index based on a combination of the analytic hierarchy process, the distance between good and poor solutions, and an expert discussion method is proposed. Using this method, on-site verification is conducted on the actual operational status of a 110 kV overhead line in Nanjing. The results demonstrate the effectiveness of the proposed method. The method proposed in this paper is not only applicable to the assessment of the health status of overhead lines, but also provides a reference for the health status assessment of other power equipment.