This paper made a further research on the index gases of coal spontaneous combustion.It studied the impact of changes of the experimental conditions,such as the experimental initial temperature,temperature-programmed rate,dry air flow,coal sample size and the weight of coal sample,etc.to the rules of the gases generation.Furthermore,Deng’s relational analysis and the slope of the relational analysis are conducted on the quantitative analysis of experimental data.Judged from the view of CO,the initial temperature of the experiment was regarded to be the critical factor,while it was the temperature-programmed rate and the weight of coal sample to C2H4.With multilateral consideration,the initial temperature was regarded as the critical factor,the temperature-programmed rate and the weight of coal sample took the second place.