Soybean mosaic virus (SMV) is one of the most destructive viral diseases in soybean [Glycine max (L.) Merr.]. The use of genetic resistance is the most effective method of controlling this disease. The objective of this research is to identify allele(s) for resistance to SMV in Jindou 1 soybean. Jindou 1 is a soybean cultivar from China, which is resistant to all seven SMV strains in the U.S. The reaction to SMV strain G1 in an F2 population derived from Jindou 1 x Essex (susceptible to all seven U.S. SMV strains) showed a 3 resistant : 1 susceptible segregating ratio, indicating a dominant allele for resistance to G1 in Jindou 1. This allele was confirmed to be different from Rsv1 in PI 96983, Rsv1-h in Suweon 97, Rsv1-k in Kwanggyo, Rsv1–m in Marshall, Rsv1-n in PI 507389, Rsv1-r in Raiden, Rsv1-t in Ogden, Rsv3 in L29, and Rsv4 in V94-5152 by a PCR-based marker. Research is in progress to test allelism of the Jindou 1 gene with the Rsv-y gene in York. If proved non-allelic, the gene for SMV resistance in Jindou 1 would be a novel allele and at a new genetic locus.