Abstract: OBJECTIVE To explore the influence of perinatal group B Streptococcus（GBS） infection on pregnancy outcomes. METHODS A total of 674 pregnant women who received prenatal check-ups in substetrics department of Xinxiang Central Hospital from Mar 2017 to Dec 2019 were recruited as the study objects. The positive rate of GBS, drug resistance, capsular serotypes, surface protein genes and pilin genes were detected, and the pregnancy outcomes were observed. RESULTS Among the 674 pregnant women, 98 were tested positive for GBS, with the positive rate 14.54%. The drug resistance rates of 98 strains of GBS to erythromycin, clindamycin and tetracycline were more than 50%, and no strains that were resistant to penicillin, cefotaxime or vancomycin were found. Totally 5 genotypes were detected from the 98 strains of GBS, there were 14（14.29%） strains with type Ia, 27（27.55%） strains with type Ib, 4（4.08%） strains with type Ⅱ, 45（45.92%） strains with type Ⅲ and 8（8.16%） strains with type IV. All of the 93 strains were detected with surface protein gens, among which rib, esp and bca gene were dominant, and the detection rate of alp2/3 was the lowest. All of the strains were detected with at least 1 type of pilin gene, and P1-2 a+P1-1 and P1-2 b were dominant. The incidence of premature rupture of membranes and premature delivery and total incidence of adverse pregnancy outcomes of the GBS-positive pregnant women were significantly higher than those of the GBS-negative pregnant women（P＜0.05）. Multivariate logistic analysis showed that age, parity, history of abnormal pregnancy, pregnancy comorbidities and positive test of GBS were the independent influencing factors for the adverse pregnancy outcomes（P＜0.05）. CONCLUSION The positive rate of GBS is high among pregnant women, which is closely associated with the adverse pregnancy outcomes. The surveillance of drug resistance and virulence genes may provide theoretical basis and data support for use of antibiotics and development of vaccine.