A new whitefly, Dialeurodes andamanensis sp. nov., is described from the Andaman Islands, India. Puparia of the new species were found infesting leaves of Strychnos wallichiana Steud. ex A. DC. (Gentianales: Loganiaceae) in Ferargunj, Andaman Islands. A map showing the type collection locality, line drawings, and images of the type specimens are also provided, and the differences in its dimorphic forms are documented.