The effects of light, temperature, pH, oxidant and reducing agents, metal ions and food additives on the stability of anthocyanins from flowers of Rhododendron pulchrum Sweet., as well as their scavenging capacity for •OH, O2-• and DPPH• free radicals and reducing power were investigated. The results showed that the anthocyanins from flowers of R. pulchrum were relatively stable in the room with natural light, at temperature lower than 45℃, and in the solution with pH ≤ 4. The addition of Na+, K+ Ca2+ metal ions, glucose, sodium benzoate, acetic acid and salt had little effect, but Cu2+, Zn2+, Fe3+, Al3+, starch and sodium glutamate showed adverse effects on the stability of the anthocyanins. The anthocyanins from flowers of R. pulchrum had a good antioxidant effect, and their scavenging capacity for •OH, O2-•, DPPH• was better than that of the same concentration of Vc.