Citrus blackfly, Aleurocanthus woglumi Ashby, is a species originated in tropical and subtropical Asia, it was introduced into many countries of the world and became serious citrus pest. The introduction of non-indigenous parasitoids has led biological control of this pest. In Mexico A. woglumi is widely distributed pest of Citrus spp. In 2004-2005, citrus blackfly had high populations in the states of Nuevo León, Tamaulipas and Veracruz: 3.304 hectares were infested. Three of four parasitic species introduced to Mexico against A. woglumi were established successfully: Encarsia perplexa Huang & Polaszek, Encarsia sp.n. (fam. Aphelinidae) and Amitus hesperidum Silvestri (fam. Platygastridae). The most important role in biocontrol of A. woglumi is done by Encarsia perplexa. Amitus hesperidum is rather rare and Encarsia sp.n. was found only in the state of Veracruz. In this period high parasitization in Tamaulipas and Nuevo León was observed. In May 2005 number of Aleurocanthus woglumi was low in these states owing to parasitoids and predators activity.