Simple SummaryEthyl formate (EF) can be a potential alternative to methyl bromide for the disinfestation of the greenhouse whitefly, a quarantine pest that affects the exportation of Oriental melon. The study found that 8 g/m3EF for 2 h at 5 °C could be used as a new phytosanitary treatment for melons (C. melo) for export with modified atmosphere packaging (MAP) to disinfest the greenhouse whitefly.AbstractTrialeurodes vaporariorum(Hemiptera: Aleyrodidae), commonly known as greenhouse whitefly, is one of the main insect pests of Oriental melon (Cucumis melovar L.) in South Korea.T. vaporariorumis of concern as a quarantine pest for the exportation ofC. meloin Southeast Asian countries. Due to future restrictions on the use of methyl bromide (MB) during quarantine, ethyl formate (EF) represents a potential alternative. In this study, we evaluated EF for its efficacy (probit-9 values) in enabling the export of Oriental melons. The probit-9 value of EF for controllingT. vaporariorumwas 3.02 g·h/m3after 2 h of fumigation. We also assessed the phytotoxicity of EF on melons when using modified atmosphere packaging (MAP) under low-temperature conditions, which is required for export and trade, to extend shelf-life. In scaled-up trials, we found 8 g/m3EF for 2 h at 5 °C to be suitable as a new phytosanitary treatment against greenhouse whitefly for exported Oriental melons when using MAP. No phytotoxic damage was found 28 d after fumigation at 5 °C in terms of five quality parameters (firmness, sugar content, mass loss, color change, and external damage).