Litchi is prone to deterioration in quality after harvest due to degradation of anthocyanins and respiratory metabolism, and chlorine dioxide (ClO2) has multiple effects on color protection and respiratory inhibition. In this study, 0.1 g (T1), 0.4 g (T2), and 1.2 g (T3) of ClO2 slow-releasing preservatives were used to treat lychees with 0 g (CK) as the control to evaluate the preservation effect by quality index, color index and anthocyanin, and correlation analysis was applied to explore the association between them. The results showed that the litchi of the T1 showed the optimal qualities. On the 7 th day, the total soluble solids and a* values of litchi in the T1 were significantly (P