In the micro-scale conditions, due to the heat transfer coupling with the combustion process within the micro-combustor, the convection and heat transfer in the micro-combustor were rather complicated issues. Based on the simulation results of the flow, heat transfer and combustion process in the micro-combustor. Dimensionless analysis method was used to calculate the dimensionless Nux number which described the convection and heat transfer intensity in the channel cross-section away from the entrance at x. Then effects of inlet parameters on the dimensionless Nuxnumber were analyzed. The formula between the dimensionless variables θ and average Nux，Rex，Prx numbers in the channel crosssection was obtained by multiple regression analysis.