The co-occurrence of COVID-19 conspiracy theories (CCT) and fear of the coronavirus (FCV) can be linked to how safe people feel and how much they endorse vaccinations. School teachers were one of the vaccination priority groups in Poland. We conducted three cross-sectional studies (N1 = 1006; N2 = 1689; N3 = 627) to find out the potential interaction effects of CCT belief and FCV in predicting sense of safety (SoS; Studies 1–3), opinions about vaccinations efficacy (Studies 2–3) and endorsement of vaccinations of children (Study 3) among school teachers. In all three studies, the belief in CCT was related to lower SoS only when FCV was low. For low CCT belief, although the belief in vaccination efficacy was higher than for CCT endorsers, it was unrelated to FCV. However, for high and average CCT belief, FCV was linked to belief in vaccination efficacy. FCV was positively related to acceptance of vaccinating children on all levels of CCT endorsement. The results are discussed in light of the available literature and their potential use in public health.