In this paper, the combustion and emission characteristics of existing gas turbines using hydrogen-doped fuel are studied. Based on the DLN1.0 combustion chamber flame cylinder, the numerical simulation method is adopted to study the influence of different hydrogen-doped ratios (a total of 7 operating conditions with volume content of H2 ranging from 0 to 30%) on the combustion process of natural gas mixture under the condition of constant thermal power and the same equivalent ratio. The distribution parameters of the flow field, temperature field and combustion product in a flame cylinder and their corresponding relationships were obtained. The results show that with the increase of hydrogen mixing ratio, the flame temperature rises, the combustion reaction zone expands, and the temperature distribution uniformity at the outlet of the flame tube becomes worse. Hydrogen mixing results in the change of local heat release, which will lead to an increasing trend of NOx emission with the increase of the hydrogen mixing ratio. Both CO and CO2 emissions decreased significantly, while H2O production increased significantly. At the same time, the dilution combustion method is proposed to solve a series of problems caused by hydrogen mixing, and the changes in combustion and emission characteristics after hydrogen mixing combustion under different equivalent ratio conditions are studied, and the optimal equivalent ratio range under each hydrogen mixing ratio conditions is calculated. The research results provide theoretical guidance for the subsequent application of hydrogen-mixed combustion technology in industrial gas turbines.