Streptococcus agalactiae colonizes the genital and alimentary canal . In pregnancy, vertical transmission of GBS to the new-born can cause neonatal sepsis, pneumonia and meningitis. The aim of this study was to work out the prevalence of GBS in pregnant women in their trimester , frequency of neonatal colonization and Antibiotics Susceptibility of the isolates recovered at the Obafemi Awolowo University Teaching Hospital Complex (OAUTHC) Ile- Ife, Osun State, Nigeria. Rectum and vaginal swabs were collected from a complete number of 24 trimester pregnant women between 35 - 37 weeks of gestation and their neonate delivered at OAUTHC both at labour ward and labour ward theatre. The samples were cultured in Todd Hewitt Broth and sub cultured on sheep agar and Chromogenic Strepto BID agar and incubated at 37ºC for twenty-four hours.