Infants and toddlers are prone to rapidly contracting illnesses, which are usually attributed to infectious diseases. Most nurseries and schools in Japan, however, refuse to accept children even with mild illnesses. For working parents, a sick child may therefore create new problems as the situation requires new day-care arrangements. To support such families, the Japanese government subsidizes construction and management of nurseries that operate especially for sick children. However, it has not been known whether most families are able to access such nurseries. To clarify the accessibility of these services, I calculated the distance to the nurseries from each of the 211,012 “blocks” (small residential areas with a median of 0.18 km²) in Japan and determined the proportion of children aged 0-4 years who lived within 3, 5, 10, 20 or 30 km of the nearest such nursery. Overall, 82.1% of these children lived within 10 km. However, the proportion was lower in northern parts of Japan such as Hokkaido and Tohoku, which have expansive land areas and low population and pediatric department densities. The proportion of children who lived within that same distance of the nearest nursery was also much lower in small towns and villages with 10,000 or fewer residents. Nurseries for sick children were not evenly distributed, and children and their caregivers in under-populated areas had to travel further to access these facilities. As the national government subsidizes such services, children and caregivers throughout Japan should have equal access to them.