Postnatal care is very crucial in the postnatal period because it is a critical period for babies. This study aims to analyze the factors related to postnatal care utilization (1 st neonatal visits) in Indonesia. The ecological analysis was conducted using secondary data from the Ministry of Health of the Republic of Indonesia report in 2018. All provinces were taken as samples. Apart from postnatal care utilization, 5 other variables analyzed as independent variables were the ANC 1 st visit, ANC 4 th visits, poverty depth index, percentage of health centers with sufficient midwives, and the ratio of gynecologist per 100,000 population. The results show there was a tendency for a positive relationship between ANC 1 st visit and 1 st neonatal visit. The higher the ANC 1 st visit coverage, the higher the 1 st neonatal visit coverage (p = 0.034). Meanwhile, there was also a trend towards a positive relationship between the ANC 1 st visit and the 1st neonatal visit. The higher the coverage of the ANC 4 th visit, the higher the coverage of the 1 st neonatal visit (p = 0.040). Moreover, poverty depth index, percentage of health centers with sufficient midwives, and the ratio of gynecologist per 100,000 population were found to have no significant correlation with 1 st neonatal visits. It could be concluded that from the 5 independent variables analyzed, 2 variables were proven to be ecologically positively related to postnatal care utilization (1st neonatal visit), namely ANC 1 st visit and ANC 4 th visit.