Abstract: Natural gas composition analysis is the most basic analysis item in the natural gas industry. The two indexes of carbon dioxide content and superior calorific value provided in GB 17820-2012 Natural Gas relate to natural gas composition analysis. The precision requirement of analysis results is an important technical parameter for natural gas composition analysis method. This paper compared the precision of natural gas conventional composition analysis methods at home and abroad, and verified the precision through experiment by using the different analysis methods. The precision reasonability and consistency of the different analysis methods were discussed. The conclusion could provide a reference for the users to choose different methods to analyze natural gas composition.