The purpose of this study is to improve the kitchen odour. To this end, the comparative experiments were conducted in the methods such as mechanical purification, electrostatic purification, adsorption cleansing, filtration purification, washing purification, composite purification, and catalytic combustion etc. The experimental results show that there is a clear correlation between the purification effect and cost, that is, the method with better purification effect has higher purification cost. Through the comprehensive comparison, it’s found that the catalytic combustion method has the best cost performance. Thus, it’s suitable for large-scale promotion.