Abstract: Vacuum concentrated coconut milk has thermodynamically instability，it is easily browning due to vulnerable high temperature and other effects. In this paper，the factors affecting vacuum concentration coconut milk browning were explored，the result showed that the mallard reaction was the main cause. In addition，by color protecting agent selection and response surface tests，the best color protection composition of vacuum concentrated coconut milk was obtained as EDTA-2Na 0.01%，citric acid 0.176%，VB-Na 0.040%.