The canine parvovirus (CPV) causes clinical signs, such as severe enteritis, dehydration, diarrhea, vomiting, leukopenia, and hair loss, which may lead to death. Vaccination is still the most important approach, as no specific treatment exists to prevent CPV. Monoclonal antibodies are valuable tools to study the pathogenic mechanisms of CPV and develop effective diagnostic reagents and pharmaceuticals. In this study, two monoclonal antibodies (MAbs) against CPV-2a were obtained through hybridoma technology by fusing myeloma cells and B cells from the spleens of mice immunized with CPV type 2a (CPV-2a). Two MAbs (CPV-330 and CPV-620) were studied on the reactivity of vaccine (CPV-2a) and field strains (CPV-new 2a, -2b, and -2c) by indirect immunofluorescence (IFA), hemagglutination inhibition test (HI), virus neutralization test (VN), and inhibition of virus growth test. Two MAbs showed similar antibody titers for HI and VN. On the other hand, CPV-330 inhibited the viral replication in Crandell-Rees Feline Kidney (CRFK) cells better than CPV-620. These CPV MAbs may provide valuable biological reagents to study the CPV pathogenic mechanisms and work as therapeutic antibodies.