Abstract:The complete cp gene of Apple stem pitting virus(ASPV)was expressed in Escherichia coli using gene recombinant method, and the antiserum was produced after the rabbit was immunized with purified protein. The titer was determined by antigen coating plate-ELISA (ACP-ELISA), and validity of the antiserum was preliminarily identified by protein A sandwich ELISA (PAS-ELISA). As a result, the cp gene was highly expressed, and the expression product could react with Anti-His antibody. Antiserum with high specificity was produced, and the titer was determined to be 1∶800. The detection results of PAS-ELISA showed, among 9 apple samples infected by ASPV, eight of them could be detected by both methods, the rest one, however, could not be detected by PAS-ELISA, but could by RT-PCR. It suggested the antiserum produced possesses applied potential to a certain extent.