用ＦＡＯ推荐的点滴法测定了南昌地区小菜蛾（ＰｌｕｔｅｌａｘｙｌｏｓｔｅｌａＬ．）的抗药性。结果表明，氯菊酯和溴氰菊酯为中抗水平（１６．３和３４．４倍），氰戊菊酯为低抗水平（３．７倍）。用浸渍法测定了南昌地区小菜蛾对乙酰甲胺磷等７种杀虫剂的敏感性。利用５种杀虫剂的田间推荐浓度，在室内和田间分别测定了对小菜蛾的效果，两者结果趋势一致。监测结果对于确定小菜蛾抗药性治理对策、用药种类决策及评价治理措施效果均具有重要意义。 The antibiotic resistance of Plutella xylostella (L.), a member of Plutella xylostella in Nanchang, was determined by the droplet method recommended by FAO. The results showed that permethrin and deltamethrin were moderately resistant (16.3 and 34.4 fold), and fenvalerate was low resistant (3.7 fold). The susceptibility of Plutella xylostella to 7 kinds of insecticides, such as acephate, was determined by impregnation method. Based on the recommended concentrations of five insecticides in the field, the effect on the diamondback moth was determined both indoors and in the field. The monitoring results are of great significance for determining the resistance management of Plutella xylostella, determining the type of drug use and evaluating the effect of the control measures.