Effects of film mulching (FM) on the total soluble solution (TSS),titratable acid (TA),the contents of 6 mineral elements (K,P,Mg,Ca,Fe and Mn) in Ponkan (Citrus reticulata) fruit was investigated using 12-year-old Ponkan as material.Results showed that FM improved fruit quality by increasing TSS and decreasing TA.Under the FM treatment of leaf,contents of K and Mn decreased significantly while contents of P,Ca and Mg obviously increased.In the juice sacs,FM decreased the contents of K and Ca significantly but increased significantly the contents of Fe and Mn at 20 days after FM.At 40 days after FM,contents of P,Mg,Ca,Fe and Mn were obviously higher than those in the control except for K lower obviously than that in the control.Results indicated that the influence of mineral accumulation in juice sacs by FM might contribute to the improvement of fruit quality via the increase of TSS and the decrease of TA.