[Objective] Screened bacterial strains which had a significant effect on mycelia and fruit body growth, and further made species identification. [Methods] Added the single strain of three bacterial strains C1, T24, T34 and four introduced bacterial strains 1B00263, 1A0081, 1A03263, 1A01082 to the casing layer, and then regular survey was mad, including the length of mycelia growth, time for primodia to emerge, number of primodia, and number and weight of mature fruit bodies. After the bacterial strains that had a significant effect on mycelia and fruit body growth were screened, molecular biology identification was further made. [Results] Adding T34 strain had a great effect on the fruit body. T34 strain not only could promote the growth of fruit bodies, but also played an important role in promoting fruit body formation and increasing the weight of individuals, indicating T34 was an ideal bacterial strain. Adding C1, T24, 1A01082, 1B00263 and 1A03263 had significant effects on fruit body growth. Meantime, adding 1A00081, 1B00263, C1 and 1A03263 could shorten the time for primodia to emerge (treatment 19.86?24.14 d and control 27.00 d). C1, T24 and T34, which had different effect degrees of on the growth of mycelia and fruit body, were further made molecular biology identification. The identification results were as follows: C1 belongs to Brevibacterium, T34 belongs to Bacillus, and T24 needs to be further determined. [Conclusion] By adding seven bacterial strains to the casing soil, we studied their effects on the growth of mycelia and fruiting body of casing soil Phlebopus portentosus. In result T34 (Bacillus sp.) was screened as the one bacterial strain that had a significant promotional effect on both mycelia and fruit body growth.