【目的】 筛选对玉米象Sitophilus zeamais和谷蠹Rhyzopertha dominica具有良好杀虫活性的挥发油及成分。【方法】 通过水蒸气蒸馏法提取挥发油，采用滤纸片熏蒸法和微量点滴法测定挥发油对玉米象和谷蠹的熏蒸及触杀活性。通过气相色谱-质谱法（GC-MS）测定挥发油的成分。【结果】 樟脑桉挥发油对玉米象24 h的熏蒸活性最好，LC₅₀为15.49 mg/L，大叶桉挥发油对玉米象48 h的熏蒸活性最好，LC₅₀为9.45 mg/L。三花桉挥发油对谷蠹24和48 h的熏蒸活性最好，LC₅₀分别为21.86和17.30 mg/L。三花桉挥发油对玉米象和谷蠹的24和48 h触杀活性最好，24 h的LD₅₀分别为33.33和6.60 μg/头，48 h的LD₅₀分别为29.67和4.13 μg/头。GC-MS分析，樟脑桉挥发油主要成分为桉叶油醇（52.17%）、(+)-α-蒎烯（9.15%）和α-松油醇（8.50%）。大叶桉挥发油的主要成分为(+)-α-蒎烯（39.91%）、α-水芹烯（9.69%）、(R)-(+)-苎烯（7.68%）、β-蒎烯（6.94%）和4-异丙基甲苯（5.84%）。三花桉挥发油主要成分为(+)-α-蒎烯（18.31%）、桉叶油醇（9.26%）、4-异丙基甲苯（8.85%）和α-松油醇（5.39%）。大叶桉挥发油中4-松油醇对玉米象熏蒸活性最好，24和48 h时的LC₅₀分别为58.65和47.37 mg/L。三花桉挥发油中α-松油醇对谷蠹熏蒸活性最好，24和48 h时的LC₅₀分别为32.87和33.03 mg/L。三花桉挥发油中α-松油醇对玉米象触杀活性最好，24和48 h时的LD₅₀分别为153.97和94.06 μg/头。三花桉挥发油中α-水芹烯对谷蠹的触杀活性最好，24和48 h时的LD₅₀分别为192.61和62.70 μg/头。【结论】 桉属植物挥发油及其活性成分可作为绿色储粮害虫防控剂的潜在选择，这类植物源杀虫剂具有良好的开发应用前景。

 [Aim]  To screen essential oils for insecticidal activity against Sitophilus zeamais and Rhyzopertha dominica . [Methods]  Essential oils were extracted by the steam distillation method, and their fumigant and contact toxicities evaluated using the filter paper fumigation, and topical application, methods, respectively. The chemical composition of essential oils was analyzed using gas chromatography-mass spectrometry (GC-MS). [Results]  Eucalyptus camphora had the highest fumigant toxicity against S. zeamais after 24 h, with an LC₅₀ of 15.49 mg/L. E. robusta essential oil had the strongest fumigant activity against S. zeamais after 48 h, with an LC₅₀ of 9.45 mg/L. E. triflora essential oil had the highest fumigant toxicity against R. dominica at both 24 and 48 h, with LC₅₀ values of 21.86 and 17.30 mg/L, respectively. E. trifloral essential oil had the strongest contact toxicity against both S. zeamais and R. dominica , with LD₅₀ values of 33.33 and 6.60 μg/adult after 24 h, and 29.67 and 4.13μg/adult after 48 h, respectively. GC-MS analysis revealed that the major components of E. camphora essential oil were eucalyptol (52.17%), (+)-α-pinene (9.15%), and α-terpineol (8.50%). E. robusta essential oil of was mainly comprised of α-pinene (39.91%), α-phellandrene (9.69%), (R)-(+)-limonene (7.68%), β-pinene (6.94%) and 4-isopropyltoluene (5.84%). The principal constituents of E. triflora essential oil were α-pinene (18.31%), eucalyptol (9.26%), 4-isopropyltoluene (8.85%) and α-terpineol (5.39%). Among the individual compounds, 4-carvomenthenol from E. robusta essential oil had the highest fumigant toxicity against S. zeamais, with LC₅₀ values of 58.65 and 47.37 mg/L at 24 and 48 h, respectively. In E. triflora essential oil, α-terpineol had the highest fumigant toxicity against R. dominica, with LC₅₀ values of 32.87 and 33.03 mg/L at 24 and 48 h, respectively. Moreover, α-terpineol in E. triflora essential oil had the highest contact toxicity against S. zeamais, with LD₅₀ values of 153.97 and 94.06 μg/adult after 24 and 48 h, respectively. In addition, α-phellandrene in E. triflora essential oil had the highest contact toxicity against R. dominica, with LD₅₀ values of 192.61 and 62.70 μg/adult after 24 and 48 h, respectively. [Conclusion]  These findings suggest that Eucalyptus essential oils and their bioactive components have potential as environmentally friendly grain storage pest control agents. Plant-derived insecticides from Eucalyptus species have promising potential for sustainable pest management applications.