Abstract: Having estimated certain parameters of the Russian wheat aphid (RWA)，Diuraphis noxia (Mordvilko)，in Xinjiang Uygur Autonomous Region，the CLIMEX model was modified to predict the suitability of different areas in China for RWA occurrence. The results showed that 18 out of the 20 selected sites in Xinjiang were in accordance with the actual distribution status of the aphid. Certain areas in Yunnan，Xinjiang，Heilongjiang，Qinghai，Xizang，Jilin，Liaoning，Gansu，Ningxia，Inner Mongolia，Shanxi and Shandong Provinces and Autonomous Regions were also favorable for RWA existence. When the duration of absence of host plants for RWA，i.e. the non-wheat growing period was taken into consideration and incorporated as a parameter in the model，all the winter wheat areas being predicted above as favorable places became unsuitable for RWA while the suitability of the spring wheat areas for the existence of RWA was reduced by 50% to 75%.

Key words: Russian wheat aphid, Diuraphis noxia (Mordvilko), CLIMEX model, favorable area, prediction, China