Vaccinations are among the greatest accomplishments of public health. However, many parents are choosing not to vaccinate. The purpose of this study was to explore the association between social media influence and parents' decisions to vaccinate their children. The health belief model indicates that individuals' likelihood of engaging in a health-related behavior is determined by their perceptions of susceptibility, severity, benefits, and barriers. The research questions addressed whether there is an association between parents' perception of their children's disease susceptibility and their decisions about vaccination, and whether there is an association between exposure to messaging from social media and parents' decision to vaccinate. A quantitative, cross-sectional research design was used. The primary dependent variable was vaccination choices, and the primary independent variable was exposure to information about vaccination through social media. Data were gathered through a questionnaire administered to 269 White parents residing in Illinois with their own children between the ages of 0 and 18 years living with them. Binomial logistic regression showed that there was not a statistically significant relationship between parents' perception of disease susceptibility and vaccination choice or between parents' vaccination choice and exposure to online antivaccine advertisements. These study findings help in defining an overall picture of vaccine hesitancy in the United States. By focusing on the predictors of this behavior, it may be possible to implement interventions to combat the antivaccine movement with the goal of increasing vaccine compliance among parents.