A low emission and high combustion load combustor is developed. The combustor reduces both NOx and unburnt fractions using rich-lean staged combustion. NOx is suppressed by fuel-rich combustion in the primary combustion chamber. Unburnt fraction is oxidized by the transition from rich to lean combustion. To avoid NOx formation, residence time nearby stoichiometry is shortened.NOx is less than 24.8 ppm(16 % O2 equivalence) or 2.26 g/kg throughout the experiments. Combustion efficiency is high regardless of the wide operating range. Specific combustion load is up to 33.6 MW/m3 without excessive NOx emission under atmospheric air condition.