The invention discloses a pesticide application method for improving peanut yield. The method comprises the following steps: (1) preparing pesticides; (2) uniformly mixing a pesticide A, a pesticide B and water based on a weight ratio of (52-58):(245-255):(72,000-78,000), and spraying the pesticides to leaf surfaces for the first time in the initial bloom stage of peanuts; (3) uniformly mixing the pesticide A, the pesticide B, a pesticide C and water based on the weight ratio of (53-57):(248-252):(18-22):(12,000-18,000), and spraying the pesticides to the leaf surfaces for the second time in a pegging stage of the peanuts; and (4) uniformly mixing the pesticide A, the pesticide B and the water based on the weight ratio of (54-56):(24-26):(13,000-17,000), spraying the pesticide to the leaf surface for the third time 15 to 20 days before the peanuts are harvested. In the method, multiple pesticide groups are adopted in the whole peanut growing period, and can be crossly and repeatedly used, so that various diseases of the peanuts can be effectively prevented and controlled, trace elements required in each growing stage of the peanuts can be fulfilled, the peanuts have more fruits with plump grains, and premature decay of the peanuts in the later stage can be effectively prevented. Furthermore, the vigorous growth can be effectively controlled, the fruit setting percentage of the peanuts can be improved, and the yield is improved by 40 percent.