A virus recovered from asparagus bean in Thailand was transmitted only to leguminous plants, including asparagus bean, cowpea, soybean, bean, pea, winged bean, and mungbean. The virus caused stunt with small leaves and shortened internodes in infected plants, and was transmitted by the aphid, Aphis craccivora, in a persistent manner, but not by mechanical inoculation. The minimum acquisition feeding periods by aphid for virus transmission were 24 hr, and the longest retention periods of the virus in the aphid were 8 days. Electron microscopic observation of ultrathin sections or leaf-dip preparations from the diseased asparagus bean did not reveal any virus-like particles. Based on these results, the virus was identified as cowpea stunt virus.