To determine the biological effects of essential oils (EOs) isolated from Cymbopogon nardus, Cymbopogon flexuosus and Cymbopogon martinii grown in Colombia against two Lepidoptera larvae, common pests in the oil palm. Specimens were captured in the field and the antifeedant activity and dermal contact lethality of EOs were measured against Acharia fusca and Euprosterna elaeasa (Lepidoptera: Limacodidae) at various concentrations 0.002-0.600 μL/cm2 and 0.002-8 μL/g, respectively. Results: All EOs exhibited strong antifeedant and toxicity activity toward Acharia fusca and Euprosterna elaeasa larvae. Cymbopogon martinii oil was the most active against both pest insect species, although all tested EOs were better than the synthetic repellent IR3535 on both insects. Colombian EOs have potential for integrated pest management programs in the oil palm industry.