An isolate of Cucumber mosaic virus (CMV), PaFM1- CMV, causing malformation on the fruit of paprika (Capsicum annuum var. grossum) was characterized based on biological reactions, serological relationships, and partial nucleotide sequence analyses. PaFM1-CMV was distinguishable from other isolates of CMV, Mf- (subgroup I) and LS-CMV (subgroup II), in terms of its reactions to some host plants. Polyclonal antibody against PaFM1-CMV showed homologous antigenic relationship with LS-CMV, however, the antibody formed a spur between PaFM1- and Mf-CMV. In the comparison of molecular size of dsRNAs of PaFM1- CMV with Mf- and LS-CMV, PaFM1-CMV had a slightly smaller RNA1 and larger RNA2, RNA3, and RNA4. When the cDNA product of PaFM1-CMV coat protein (CP) gene was digested with some restriction enzymes, the fragment pattern was identical with that of LS-CMV. The nucleotide and amino acid sequences of PaFM1-CMV CP gene were 99.5% and 98.6% identical with LS-CMV, respectively. The data indicate that PaFM1-CMV belongs to subgroup II of CMV, which is the first report in Korea.