The invention provides a combustion chamber structure of a ground combustion engine and a staged combustion organization method of the combustion chamber structure. A small flame tube is independently adopted by the front portion of an on-duty combustion area, and the tail end of the small flame tube is provided with a contraction section. A big flame tube provided with a flame stabilizer is adopted by a rear main combustion area. In this way, airflow interference and flame interference to the main combustion area and the on-duty combustion area can be avoided, a stable ignition source is formed for the on-duty stage, and the combustion stability of a combustion chamber is improved. Through the aerofoil blade design at the outlet of a main cyclone cylinder, fuel in the main cyclone cylinder and air are subjected to cyclone mixing for the second time; meanwhile, by means of the inward expansion of the main cyclone cylinder and the flame stabilizer on the downstream portion, mild combustion can be conducted stably in the combustion chamber, the combustion uniformity is improved, the NOx emission is greatly reduced, the combustion efficiency is improved, and backfire is prevented.