【目的】 茶尺蠖Ectropis obliqua Prout是茶树上的重要害虫，本研究旨在研究茶园常用农药联苯菊酯与茚虫威两种农药对该虫中肠细胞结构及血淋巴酶活性的影响，为日后更好防治该虫提供理论基础。【方法】 采用浸梢法在室内测定了5龄茶尺蠖幼虫对联苯菊酯与茚虫威的半致死浓度LC₅₀值。采用LC₅₀浓度药液进一步处理茶尺蠖，通过透射电镜观察了联苯菊酯与茚虫威对茶尺蠖中肠细胞结构的影响，以及血淋巴中谷胱甘肽-S-转移酶（GSTs）、乙酰胆碱酯酶（AChE）和羧酸酯酶（CarE）3种解毒酶的酶活性变化。【结果】 联苯菊酯与茚虫威对5龄茶尺蠖幼虫的LC₅₀值分别为5.884 mg^.L^－1与0.268 mg^.L^－1。透射电镜显示，中肠柱状细胞的微绒毛大量解体、散乱分布于肠腔中，胞内细胞器向顶膜转移，并发生明显的形变。酶活检测结果表明，经联苯菊酯处理后，GSTs的酶活基本不变，而AchE和CarE的酶活性被显著诱导。经茚虫威处理后，GSTs、AchE和CarE的酶活性均被显著抑制。【结论】 联苯菊酯与茚虫威不仅具有破坏茶尺蠖中肠柱状细胞的微绒毛，使各细胞的牢固性与紧密性缺失，还会破坏柱状细胞内部的细胞器功能。联苯菊酯在血淋巴中的解毒代谢与酯酶（AChE和CarE）有关，与转移酶（GSTs）无关，而茚虫威与酯酶（AChE和CarE）和转移酶（GSTs）两者均有关。

[Objectives]  To investigate the effects of bifenthrin (BIF) and indoxacarb (IND) on the midgut cell structure and hemolymph detoxification enzyme of Ectropis obliqua Prout, a pest of tea plantations. [Methods]  The tail immersion method was used to expose 5^th instar larvae of E. obliqua to the median lethal concentration (LC₅₀) of bifenthrin and indoxacarb and subsequent changes in structure in midgut cells were observed with transmission electron microscopy. The activities of detoxification enzymes in hemolymph, including glutathione-S-transferase (GSTs), acetylcholinesterase (AChE) and carboxylesterase (CarE), were also quatified. [Results]  The LC_50s of BIF and IND for 5^th instar E. obliqua larvae were 5.884 mg^.L^－1 and 0.268 mg^.L^－1, respectively. Transmission electron microscopy revealed that BIF and IND induced disintegration of the microvilli in columnar cells, which became scattered in the intestine. In addition, intracellular organelles were transferred to the top cytomembrane and became obviously deformed. BIF induced an obvious increase in AchE and CarE activity but no significant change in GSTs activity, whereas IND significantly inhibited GSTs, AchE and CarE activity in hemolymph. [Conclusion]  Bifenthrin and indoxacarb damaged the structure of midgut columnar cells in E. oblique by destroying the microvilli and disrupting organelle function. In addition, the detoxification of bifenthrin in hemolymph is related to esterase (AChE and CarE), but not transferase (GSTs) activity, whereas the detoxification of indoxacarb is related to both esterase (AChE and CarE) and transferase (GSTs) activity.