Taking‘Tainong No.1’passion fruit as the testmaterial，the effects of spraying different concentration gradients of CaCl2 on the growth and citric acid accumulation of passion fruit were investigated. The results showed that compared with thecontrd(CK)，the single fruit weight of the two concentration gradients of CaCl 2treatmentdecreased，the fruit shapeindex，edible rate and soluble solidsincreased，and the decrease rate of single fruit weight and soluble solids content slowed down during postharvest storage. The results of citric acid content analysis showed that 2% CaCl2 treatment significantly promotedthe accumulation of citric acid at fruit ripening stage，and 4% CaCl 2 treatment promoted the accumulation of citric acid during storage. The results of correlation analysis of enzyme activity showed that phosphoenolpyruvate carboxylase and aconitic acid metabolic enzyme mainly regulated the accumulation of citric acid and were the key enzymes for citric acid accumulation. The results could have important theoretical basis and practical significance for understanding the accumulation of citric acid in passion fruit and future quality improvement.