Abstract: The avinilent and bacteriocinogenic strain Tm3 of Ralstonia solanacearum had inhibiting effect on tomato virulent strain Ttn46 and could induce hypersensitive response(HR) in tobacco plants. ItS ability to protect tomato plants from bacterial wilt was investigated in greenhouse and the results indicated that strain Tm3 had a good effect on the biological control of tomato bacterial wilt. The possible mechanisms for the protechon were both antibiosis of bacteriocin and induced resistance of hosts.