S-Glycoproteins have been thought to play a role in the self-incompatibility in Brassica plants. Two cDNAs encoding S-glycoproteins were isolated from stigmas of two strains of Brassica campestris. Their amino acid sequences are highly homologous to each other. However, the numbers of the potential glycosylation sites are different, although most of them are conserved. In the middle part of the sequences, there are two supervariable regions which might contribute to the specificity of each S-glycoprotein. Genomic Southern analysis showed many bands hybridizing with cDNA of S-glycoproteins in various Brassica species including self-compatible species.