Abstract: LNG has been steadily increasing its share of the global gas trade. The United States and European countries have studied the interchangeability of natural gas according to specific situations and provided results of the relevant studies. In China, the import of LNG is steadily increasing, but the problems regarding quality and interchangeability were not fully understood and resolved. In this paper, a study on applicability of Weaver indices has been completed. The experiments were conducted for 17 typical gas appliances and 11 natural gas sources with 187 test conditions. Comparing the experimental results with the results predicted by Weaver indices, it suggested that the limits of Lifting J_L need to change to ≥0.95, Incomplete Combustion J_I need to change to ≤0.04 and the limit of AGA index Lifting I_L change to ≤1.05.