According to high failure rate and low reliability of intelligent watt-hour meter in the typical environment of high cold, high altitude, high humidity and heat, high salt fog, high dry and heat, this paper analyses the influence factors of typical environment on the operation reliability of intelligent watt-hour meter, chooses hierarchical structure as the basic data structure of reliability index system , and establishes an index system for evaluating the reliability of intelligent watt-hour meters in typical environments. In this paper, based on analytic hierarchy process and entropy theory, an improved entropy weight method is proposed to quantify the reliability index of intelligent watt-hour meter and compute the weights in typical environment. In this paper, the reliability index system and index quantification method of intelligent watt-hour meter based on regional differences, effectively perfects the evaluation system of intelligent watt-hour meter, improves the management level of intelligent watt-hour meter in the State Grid, provides technical support for the State Grid Corporation to carry out differentiated bidding and process control of watt-hour meter manufacturing.