The combustion and emission characteristics of existing gas turbines using hydrogen-doped fuel were studied. Based on the DLN1.0 combustion chamber flame cylinder, the numerical simulation method was adopted to study the influence of different hydrogen-doped ratios (a total of 7 operating conditions with volume fraction 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 NO_x emission with the increase of the hydrogen mixing ratio. Both CO and CO₂ emissions decrease significantly, while H₂O production increases significantly. At the same time, a proposed dilution combustion method was adopted to solve a series of problems caused by hydrogen mixing, the characteristics changes were studied after hydrogen mixing combustion under different equivalent ratios, and the best equivalent ratio was calculated under each hydrogen mixing ratio. The research results provide theoretical guidance for the subsequent application of hydrogen-doped combustion technology in industrial gas turbines.