Abstract: Liquid silicon fertilizer was applied to green crisp plum trees using two different methods: root irrigation and foliar spraying．After fruit ripening, fruit weight, soluble solids, hardness, sugar composition, acid composition, and vitamin C content were measured．Results indicated that silicon fertilizer application significantly enhanced quality indicators such as fruit weight, soluble solids, fruit sugar, and vitamin C content compared to control group．Root irrigation treatment had an effective silicon dosage of 34 g（0.4 kg silicon fertilizer）, while foliar spraying treatment had an effective silicon dosage of 1.92 g（16 mL of silicon fertilizer）, which showed superior effects．