The relative feeding amount of cowpea aphid Aphis craccivora Kochon 20 varieties of cowpea Vigna sp.were studied by measuring the ra-diacitivity of aphids feeding on NaH_2 ~(32)PO_4 labelled cowpea plants,andthe area of honeydew excreted by aphids on filter paper stained withninhydrin.The results showed that among the 20 cowpea varieties,'Yan Dai Hong','Zhu Yan Bai','Chao Yang Xian','San ChiHong','Si Ji Qing',and 'Huang Hua Qing' were highly resis-tant,while 'Zhi Jia Qing','Lu Bai','Hei Zi Duan','Bai YouDou',etc....