The effectiveness of acetylated glyceride (acetic and fatty acid esters of glycerol) developed as an adult repellent was clarified by observing the host selection behavior of the sweet potato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on treated plant leaves. In a choice test between treated and untreated grape tomato leaves, it was observed that almost the same number of adults landed on the leaves, but the retention rates of adults settling under the leaves were 27% and 95%, respectively. Repellent behavior was induced within 5 sec of the adult’s landing on the plant surface. The repellent led to a large reduction in the number of eggs laid on grape tomato leaves as compared to untreated leaves. However, no adulticidal activity by direct foliar treatment and no insecticidal activity against the progeny by contact treatment were found on cucumber leaves.