In the past, waste policies’ priority fell in stable treatment. Since the enactment of the Framework Act on Resource Circulation (FARC) in 2018, waste policies have emphasized more the recycling of resources and efficient recovery of energy. On the basis of Appendix 6 of Article 18 of the FARC, an analysis of the combustible contents of mixed waste is now required due to the difficulty in separating combustible and non-combustible waste. This study identified that the optimum conditions for changing various factors such as sample size, quantity, and analysis temperature by waste type. As a result, the size of the sample is 1 mm or less, and the quantity of the sample is 5 g or more. The target waste confirmed the burning temperature to be 300 ~ 600℃, and the analysis temperature of the combustible and ash contents was set at 600 ± 25℃. In addition, standard test methods for the combustible and ash contents in waste are presented.