This study investigated the effect of an intervention regarding the use of simulations in science teaching on primary school preservice science teachers’ ( n = 36) self-assessed technological, pedagogical, and content knowledge (TPACK). The connection of their self-assessed TPACK on their views on the usefulness of simulations in science teaching and on their disposition toward integrating simulations in their teaching was also studied. The results showed statistically significant differences between preservice teachers’ pre- and posttests in content knowledge, pedagogical knowledge, and TPACK domains. Preservice science teachers’ technological knowledge correlated with their views on the usefulness of simulation and disposition toward integrating simulations in teaching. The implication for science teacher training is that more attention should be paid to developing preservice teachers’ beliefs about their technological knowledge throughout their teacher training in order to encourage them to use simulations in science teaching.