In this paper，some modifications on theoretical combustion temperature are made，and a model for calculation of theoretical combustion temperature based on the fuel(coke and coal) calorific value is developed. In the model，the incomplete combustion heat that is released by the fuel can be calculated by difference between the complete combustion heat and the heat loss because of incomplete combustion.Finally，the influence of some factors，such as coal species，coal ratio，oxygen enrichment ratio，on the theoretical combustion temperature are analyzed.