The aim of this study is to examine the factors affecting negative attitudes (vaccine hesitancy and anti-vaccination) towards vaccines. Data of 4004 people were collected online. Although vaccine hesitancy and anti-vaccination attitudes are two different concepts, there is a strong positive relationship between them. In this study, explanatory factor analysis and confirmatory factor analysis are used for vaccine questions. Then, quantile regression models at 10p, 50p and 90p values were calculated separately for these two variables (vaccine hesitancy and anti-vaccination). As a result of the estimation, age, gender, education, household income, belief in conspiracy theories, political views, religious involvement are significant predictors. In addition, trust in science, doctors, the government, vaccine companies, COVID-19 vaccines and herbal treatments are other predictive variables. Negative attitudes towards vaccines are relatively higher among the poor, unemployed and socio-economically disadvantaged groups. To reduce negative attitudes towards vaccines, it is important to inform society based on the results of reliable scientific research, to follow transparent policies that will reduce the doubts in people’s minds, and to maintain effective communication policies.