Effects of relevant factors on anthocyanin synthesis in the pericarp of litchi ( Litchi chinensis Sonn. cv. Feizixiao) was studied. The results showed that before coloration, both soluble sugar and anthocyanin increased rapidly, and sugar might initiate anthocyanin synthesis. PAL did not appear to be the key enzyme for anthocyanin synthesis. The effect of pH on anthocyanin synthesis was complex and further study is required.