Long-term cultivated soil (tomato) was selected as the research object to seek high yield,high efficiency and water-saving irrigation methods while minimizing greenhouse gas emissions as much as possible. Three irrigation methods (mulched drip irrigation,drip filtration irrigation and furrow irrigation) were investigated for soil greenhouse gas (N_2O,CO_2 and CH_4) emission characteristics,in order to reveal the relationship between greenhouse gases and soil temperature (5 cm) and moisture. Based on the research results,we put forward the concept of 'yield gas ratio' to compare the cumulative emissions of greenhouse gases. The results showed that: (1) the total N_2O emissions during the tomato growing season decreased with the order of furrow irrigation (25.33 kg/hm~2) > mulched drip irrigation(23.87 kg/hm~2) > drip filtration irrigation (10.04 kg/hm~2). When soil temperature was appropriate,N_2O emission flux was extremely significantly correlated with soil moisture (P < 0.01). (2) CO_2 emissions increased with increased temperature and plant growth. The CO_2 total emissions decreased with an order of drip filtration irrigation (11.84 t/hm~2) > furrow irrigation (10.45 t/hm~2) > mulched drip irrigation (9.53 t/hm~2). The CO_2 emission fluxes of mulched drip irrigation and drip filtration irrigation were extremely significantly correlated with soil temperature (P < 0.01), and the furrow irrigation was also significantly correlated with soil temperature (P < 0.05). (3) Overall,CH_4 was a sink during the tomato growing season. The CH_4 total absorptions decreased with an order of drip filtration irrigation (1.98 kg/hm~2) > mulched drip irrigation (0.93 kg/hm~2) > furrow irrigation (0.71 kg/hm~2), and CH_4 emission flux had significant correlation with soil moisture. In summary,using plastic mulched drip irrigation can not only realize goals of high yield,high efficiency and water conservation,but also achieves the least amount of greenhouse gas emissions. Besides,it attains the greatest degree of soil greenhouse gas emission reductions and can slow global warming. In conclusion,the plastic mulched drip irrigation is the best method of irrigation.