Abstract: The niche breadths of natural enemies of the wheat aphids in wheat, barley and oat fields in Tacheng and Ili, Xinjiang Uygur Autonomous Region were estimated on the basis of investigation in 1990. Coccinellids had the longest temporal niche in wheat fields in both Tacheng and Ili. Syrphids and coccinellids in Tacheng wheat field showed greatest overlap in their temporal niches, indicating the existence of a keen competition. In wheat fields in Ili, syrphids had the greatest spatial niche, coccinellids had the largest tempo-spatial niche, Leucopis spp. And coccinellids had the largest niche overlap in spatial dimensions, and aphelinids and Leucopis spp. Showed the maximum overlap in their spatial and tempo-spatial niches. Moreover, niches of natural enemies of wheat aphids in barley and oat fields were also discussed.

Key words: wheat aphids, natural enemy, niche, Xinjiang Uygur Autonomous Region