Abstract: Through studying promotion and application of mechanical weeding technology under "double reduction" policy（reducing use of fertilizers and pesticides）in agriculture, research background and significance of mechanical weeding technology under the policy in agriculture were analyzed．By combining methods of literature review, telephone interviews, and field observation, definition and goals of "double reduction" policy were elaborated, and classification and application of mechanical weeding technology were introduced．At same time, impact of mechanical weeding technology promotion under "double reduction" policy in agriculture was analyzed, a case of mechanical weeding promotion and application in Yi'an County, Heilongjiang Province were profiled, and strategies and measures for promoting and application of mechanical weeding technology were proposed．A reference and guidance for decision-making and related policy formulation of mechanical weeding industry was proposed．