Abstract: To screen the antagonistic actinomycetes against Phytophthora parasitica from tobacco rhizospheric soils in order to control tobacco black shank, the antagonistic effects of actinomycetes from rhizospheric soils in Luoyang tobacco-growing areas and their fermentation broths against P. parasitica were determined by improved plate confrontation test and mycelial growth rate method. Dominant antagonistic strains were identified by morphological and biochemical features and 16S rDNA analysis. The results showed that 227 strains of actinomycetes were isolated, in which the inhibition rates of the fermentation broths of 8 strains against P. parasitica reached 100%, therefore the 8 strains were determined as the dominant antagonistic strains. The results of morphological and biochemical features and 16S rDNA analysis indicated that YY75, SX92 and SX59 were identified as Streptomyces lucensis, S. coralus and S. aureoverticillatus, respectively. YY124 and YY135 were identified as S. nobilis. LN204, LN221 and LN247 were identified as S. rochei. The 8 dominant strains all belonged to Actinobacteria, Actinobacteria, Stretomytales, Streptomycetaceae, Streptomyces.