Snow Mountain Virus (SMV) belongs to the Norovirus genus of the Caliciviridae family. SMV is a genogroup II (GII) reference strain of human enteric caliciviruses associated with epidemic gastroenteritis. The positive sense RNA genome sequence of SMV was determined to be 7,537 nucleotides in length excluding the 3' polyadenylated tract. The genome is organized into three open reading frames. Pairwise sequence alignments showed SMV ORF1 is highly conserved with other GII noroviruses, and most closely related to GII strains Melksham and Hawaii viruses. Comparative sequence analyses showed the SMV is a recombinant norovirus. VP1/NP2 proteins assembled into virus-like particles (VLPs) when expressed in insect cells by a recombinant baculovirus. Characterization of one clone that expressed VP1 but failed to assemble into VLPs, identified histidine residue 91 as important for particle assembly.