The invention belongs to the technical field of flue-cured tobacco cultivation, and particularly relates to a method for effectively reducing N2O emission in flue-cured tobacco cultivation soil. The method includes the following steps: performing soil deep ploughing during soil preparation in advance: deeply ploughing cultivation soil; ridging and pond digging: ridging the soil subjected to deep ploughing; applying biochar: applying straw biochar into the pond in the step (2); irrigation and fertilization management: carrying out field irrigation and fertilization management by adopting a drip irrigation water and fertilizer integrated technology, and in the drip irrigation process, performing single-time irrigation with the quota of 2-3mm and 1.2-1.8 L/plant; according to the invention, on the basis of guaranteeing the yield and the output value of the flue-cured tobacco, obvious emission reduction of N2O in the tobacco field can be achieved.