Essential oil of Pogostemon cablin (Blanco) Bentham (Lamiaceae), known as patchouli oil, has been reported to display strong insecticidal activities, but few studies have focused on the insecticidal activity of its principal constituent, pogostone. The present work was designed to evaluate the insecticidal, repellent, and antifeedant activities of pogostone against Myzus persicae (Sulzer) (Hemiptera: Aphididae). In a choice test, pogostone had strong repellent activity against M. persicae. Pogostone also showed pronounced contact toxicity (LC₅₀ of 1,694 mg/L) to this piercing—sucking insect, as well as powerful antifeedant activity. Pogostone may partly account for the insecticidal activity of patchouli oil, but it also has other valuable properties. This study demonstrated the potential of pogostone as a promising candidate for managing agricultural insects.