〔Abstract〕 Objective To explore the molecular characteristics of four CAMP negativeStreptococcus agalactiae(S.agalactiae) in whole genome sequencing. Methods The identification of suspicious bacterial strains was conducted using matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS). For the strains confirmed asS.agalactiaethrough identification, further CAMP experiments were conducted. For CAMP negative strains, whole genome sequencing was performed using MGI DNBSEQ-T7 and MinION Flow Cell sequencing platforms. Subsequently, multi-locus sequence typing(MLST), virulence genes and resistance genes of the strains were compared and analyzed using various databases. Phoenix M50 fully automatic drug sensitivity analyzer was employed to determine the sensitivity of the bacterial strains to commonly used antibiotics. Results Four CAMP-negativeS.agalactiaestrains were included. Whole-genome sequencing analysis revealed that all four CAMP-negativeS.agalactiaestrains belonged to the ST862 type. These strains harbored 22 virulence genes associated with capsular polysaccharides, β-hemolysin, and hyaluronidase, as well as seven resistance genes linked to macrolides, lincosamides, polypeptides, and aminoglycosides. Antimicrobial susceptibility testing revealed that CAMP-negativeS.agalactiaewas susceptible to penicillin G, cefepime, cefotaxime, and vancomycin. However, three strains exhibited resistance to erythromycin, and one strain demonstrated resistance to clindamycin. Conclusion Four CAMP negativeS.agalactiaeof the ST862 type possess multiple virulence and drug resistance genes, showing high resistance to erythromycin, warranting clinical attention.