Research implicates spatial ability in science, technology, mathematics, and engineering (STEM). In both STEM enrollment and spatial cognition gender differences in favor of males are observable. Stereotyping may play an important role in this context. This study investigated gender stereotypes related to spatial ability in preschool children, representing the first exploration of implicit and explicit stereotypes and their potential association with spatial task performance in this age group. The participant pool comprised 138 children aged 4 to 6 years. The research design involved three main components: an implicit association task, a brief questionnaire assessing explicit stereotypes, and a chronometric mental rotation task. Results revealed that preschool children hold explicit gender stereotypes linking spatial ability more strongly to boys than girls, with boys exhibiting more pronounced stereotypes. Evidence of implicit stereotypes was found, though subgroup analyses did not consistently confirm their presence. While no clear correlation between stereotypes and mental rotation performance emerged, the study suggested that implicit stereotyping may impact mental rotation accuracy differently for girls compared with boys. The primary conclusion is that stereotypic beliefs about spatial ability are already present in preschool children, though no discernible relationship with actual spatial ability was observed at this early stage. The findings underscore the importance of addressing and challenging gender stereotypes in early childhood education.