The effects of pH, temperature and oxidizing and reducing agents on color and stability of anthocyanin from red radish (Raphanus sativus L.) was investigated. The results showed that with the increase of pH value, the color of anthocyanin is changed from red to brown and the characteristic absorption peak at 510 nm disappear. The stability of anthocyanin from red radish is significantly affected by pH value, and its degradation rate is the fastest at pH 3.0. Low temperature is effective in maintain the stability of anthocyanin from red radish. H2O2 significantly promotes degradation of the anthocyanin, while ascobic acid (AsA) and dithiothreitol (DTT) delay degradation and discoloration of the anthocyanin.