The invention relates to a pest control method applicable to autumn cabbage in northern area. The method comprises the following steps: in a late rosette stage to a whole cabbage roll formation stage of the autumn cabbage, diluting phoxim emulsifiable concentrate with a concentration of 50% by 100 to 120 times so as to obtain a liquid medicine, then subjecting absorbent cotton balls to absorbing the liquid medicine, filling the absorbent cotton balls into special medicine containers, and arranging the special medicine containers in a vegetable field with different densities and heights by utilizing specially-processed fixing devices and rainproof devices; thus, through natural volatilization of the liquid medicine into air in the vegetable field, the purpose of repelling adult pests which fly into the vegetable field for spawning is achieved, and occurrence of pest attack in the vegetable field is effectively prevented.