This study examined the associations between multiple childcare arrangements and young children’s health problems. This study used three waves of the Early Childhood Longitudinal Study—Birth Cohort, collected from a nationally representative sample of children when they were 9 months old, 2 years old, and 4 years old (N = 7,150). ‘Multiple childcare arrangements’ was defined and measured by the number of non-parental childcare arrangements that occurred on a regular basis. During each wave of the data collection, the mother reported the number of regular childcare arrangements by three types: relative care, non-relative care, and center-based care. These numbers were summed to calculate the total number of arrangements. The mother also reported the incidence of ear infections, gastrointestinal illnesses, asthma diagnosis, and unintentional injuries of the child. Random effects and fixed effects regression models were used to estimate the association between the number of childcare arrangements and measures of early childhood health problems. Increases in the total number of childcare arrangements were associated with an elevated risk of ear infections, gastrointestinal illnesses, and diagnosed asthma in children. Further analysis indicates that increases in both the number of center-based care and non-relative care (but not relative care) arrangements can lead to a greater chance of health problems in young children. Multiple childcare arrangements are associated with communicable illness and diagnosed asthma in early childhood and appear to be a risk factor for health problems in early childhood.