Background. The incidence of vaccine hesitancy is increasing in many countries. This study aims to determine parents` attitudes and related factors regarding COVID-19 vaccine acceptance for themselves and their children aged 12-18. Methods. A cross-sectional survey was conducted on parents between 16th November and 31st December 2021, after COVID-19 vaccines were initiated for children in Türkiye. In the survey, the sociodemographic characteristics of the parents, whether they and their children were vaccinated against COVID-19, and if not, the reasons for this were asked. Multivariate binary logistic regression analysis was used to evaluate the factors affecting parents` refusal to vaccinate their children for COVID-19. Results. Three hundred and ninety-six mothers and fathers were included in the final analysis. Overall, 41.7% of parents reported vaccine refusal for their children. COVID-19 vaccine refusal was higher in mothers younger than 35 (β = 6.5, p = 0.002, 95% CI: 2.0-23.1), children aged 15 and younger (β = 2.3, p = 0.001, 95% CI: 1.4-3.7). Concerns about the side effects of the COVID-19 vaccine (29.7%) and their children not wanting to be vaccinated (29.0%) were the most common causes of COVID-19 vaccine refusal. Conclusions. In the present study, the rate of children not vaccinated due to COVID-19 vaccine refusal was relatively high. Parents` concerns about vaccine side effects, as well as their children`s unwillingness to be vaccinated, suggest that both parents and adolescents should be informed about the importance of COVID-19 vaccines.