Abstract: To explore the potential of antibiotic biocontrol agents Shenqinmycin to control tobacco black shank disease, the inhibitory effects of Shenqinmycin on mycelial growth, sporangia formation and zoospores release of Phytophthora nicotianae was investigated in vitro. The effects of Shenqinmycin on the control of tobacco black shank and the growth of tobacco plant were determined based on greenhouse experiments and field trials. The results showed that Shenqinmycin had the best inhibitory effect on sporangia formation and zoospores release of P. nicotianae in Yinshui with EC₅₀ of 0.31 and 0.35 μg/mL, respectively. The results of greenhouse pot experiment indicated that the control effect of 1% Shenqinmycin suspension on tobacco black shank at 15 g a.i./ha was 84.37%, which was significantly higher than that of 25% metalaxyl (56.33%) and 50% dimethomorph (80.55%), whereas the field trial results were basically consistent with the control effect of greenhouse experiments. Field efficacy trials in Mianning and Zhucheng showed that the application of Shenqinmycin can significantly reduce tobacco black shank to occurrence, and the control effect on tobacco black shank in Liangshan and Zhucheng was 90.49% and 82.93%, which was significantly higher than the control agents metalaxyl (71.89%, 38.87%) and dimethomorph (78.42%, 69.01%). In addition, Shenzinmycin has better effects on the increase of plant height, stem diameter, effective leaf number and photosynthetic rate than that of metalaxyl and dimethomorph. The results of the present study indicate that Shenqinmycin can be used as an alternative agent for metalaxyl and dimethomorph to control tobacco black shank.