【Objective】The present experiment was conducted to study the sensitivity of Phytophthora parasitica var. nicotianae to metalaxlyl in Guangxi in order to apply the proper control measures for its spread. 【Method】Sensitivity of 196 Phytophthora parasitica var. nicotianae strains isolated from the main tobacco areas of Guangxi to metalaxlyl was tested by observing the growth rate of fungal strains. 【Result】EC50 values of 196 isolates ranged from 0.0691 to 1.0243 μg/mL， and the mean EC50 value was 0.3618±0.0297 μg/mL. The isolate TL05 from Tianlin County was the most sensitive one， with the EC50 value of 0.0691 μg/mL， while the isolate ZXHD12 from Huadong Town， Jingxi County was the most resistant， with the EC50 value of 1.0243 μg/mL. A significant difference among the sensitivities of isolates from different sites has been observed. The isolates from Nandan and Tianlin County were the most sensitive， while those from Longlin， Jingxi， Debao and Fuchuan County were the most resistant. The frequencies of sensitive， intermediate and resistant isolates to metalaxyl were 1.53， 66.84 and 31.63%， respectively. 【Conclusion】A low level of resistance to metalaxyl has been observed in Phytophthora parasitica var. nicotianae in Guangxi. It is， therefore， suggested that metalaxyl should be alternated with other fungicides for proper control of the tobacco black shank.