A cross sectional study was conducted on equine from November 2010 to February 2011 to determine the seroprevalence of African Horse Sickness Virus (AHSV) antibodies and identification of potential risk factors in equine population in selected areas of Arsi and Bale zones. A total of 480 serum samples were collected. Competitive ELISA test was employed to determine the presence of African Horse Sickness (AHS) antibodies. The seroprevalence of 28.63 and 14.23% were found in the Arsi and Bale zones, respectively. The apparent seroprevalence was found to be 24.60% in donkey, 20.34% in horses and 20% in mules. The overall seroprevalence of AHS virus was found to be 21.45%. There was no significant variation between the horse, donkey and mules in the seropositivity (p>0.05). Statistically significant difference (p<0.05) in the seroprevalence was observed in the different study area, confirming the existence of agro-ecology variation in the occurrence of AHS, thus higher seroprevalence of AHS was documented in midland (31.38%) followed by highland (15.06%). Significant variation was not observed in seroprevalence among age groups and sex of equine. All age groups as well as male and female of equine population were equally affected. Knowledge base of equine owner about AHS, Clucoides vector and mode of transmission of the disease in the study areas were assessed through structured questionnaire. The survey result indicated that almost all equine owners did not know about Clucoides vector and mode of transmission. Therefore, there should be awareness reaction about AHS and Clucoides vector among the people through an organized extension package to the present study areas.