Abstract：Taking field experiment method，this paper studied the synergistic effect of a new biological additive，3% lecithin · vitamin E on controlling tomato gray mold by fungicide pyrisoxazole 25% emulsifiable concentrate（EC）and 38% pyraclostrobin · boscalid water dispersible granules（WG）．The results showed that the final control effects of pyrisoxazole 25% EC 1 605 mL · hm-2 + 3% lecithin·vitamin E 180 mL · hm-2， 38% pyraclostrobin · boscalid WG 750 g · hm-2 + 3% lecithin · vitamin E 180 mL · hm-2 on gray mold caused by Botrytis cinerea on tomato leaves and fruits were significantly higher than that of the single treatment of corresponding fungicide，and the tomato yield was also significantly increased．After 20% reduction of these 2 fungicides and then adding 3% lecithin · vitamin E，there were no significant differences between the control effect of gray mold on tomato leaves and fruits，yield by single and full dose treatments of each of the 2 fungicides．Also there is no phytotoxic effect．So it is safe to use．
