Group B Streptococcus (GBS) is a leading cause of meningitis and sepsis in infancy, but burden of disease data are scarce for Asia. We performed two hospital-based, prospective, descriptive, observational studies using similar protocols in the Philippines and Thailand to evaluate neonatal GBS disease epidemiology. Infants aged <90 days with a GBS-positive culture from normally sterile sites using routine microbiological standards were eligible for inclusion. Awareness of GBS symptoms was raised by informing all women at delivery and follow-up for 90 days post-delivery. Infections were classified as early onset disease (EOD) if they occurred within 6 days of birth and late Onset disease (LOD) if they occurred 7-89 days after birth. Due to ethical requirements in Thailand, consent for study participation, including periodic post-discharge telephone calls, was obtained at delivery. Parents in the Philippines gave consent for study participation at case identification. The clinical outcomes of GBS infections were recorded. During the 6-month study period, two cases (one fatal) of EOD were identified among 8,409 live births at the study hospitals in Thailand and three cases (two fatal) of EOD were identified among 11,768 live births reported at the study hospitals in the Philippines. Incidence rates per 1,000 live births were 0.2 (95% CI: 0.0-0.8) and 0.3 (95% CI: 0.1-0.8) in Thailand and the Philippines, respectively. There were no cases of reported LOD. The low number of cases precluded analysis of serotype distribution and case fatality rates. Large epidemiological studies are needed to better understand the factors influencing GBS infection incidence in Asia.