The invention relates to a planting method for improving the sugar content of passion fruits. The variety of the planted passion fruits is 'Tainong No.1', and the planting method comprises the steps of land selection, soil preparation, planting, frame erection, reshaping and pruning, fertilizer and water management, field management and prevention and control of diseases and insect pests. By the adoption of the planting method for improving the sugar content of the passion fruits, a fertilizer containing sugar and fermentation broth prepared through fermentation of human excrete and containing a sugar fertilizer are irrigated in a drop mode before blooming and during fruit forming, the average single-fruit weight of produced passion fruits is 63 g, the maximum weight is 125 g, fruit juice is reddish yellow and has heavy flavor, the acidity is 2.14%, the sweetness is up to 30% Brix, the fruit juice rate is up to 34%, color and luster are bright, the yield is high, no pollution exists, and five-time harvesting can be performed in one year.