Effect of 290 isolates of bacteria from cucumber rhizosphere were studied as potential biocontrol agents for control of cucumber wilt disease caused by Verticillium dahliae. 37% of bacterial isolates inhibited growth of V. dahliae. Inhibition ability on fungal growth was varied among bacterial isolates, ranged from 12.5-49.93% in dual culture test, from 22.24-84. 54% in volatile test and 60.84-96. 40% in antibiotic tests. Effective bacterial isolates were identified as Bacillus subtilis (B1 B2, B4), B. pumilus (B3), Pseudomonas fluorescens bv. III (P1) and P. fluorescens bv V (P2, P3, P4), according to biochemical, morphological, nutritional and physiological testes. spore germination of V. dahliae was decreased by P. fluorescens bv III (P1) and P. fluorescens bv V (p2, P3, P4) according to siderophore production test. In fungicide testes on bacterial isolates Benomyl, carbendazim, thiofanate metyl and captan no observed any inhibition on growth of bacterial isolates. B. subtilis (B1) was decreased disease severity, increased plant height, shoot and root dry weight in the infected and non infected to V. dahliae in the greenhouse conditions. In seed coating and soil drenching methods similar result had been obtained using B. subtilis (B2).