Surrounding the national emphasis on improving STEM education, effective STEM educators are required. Connected, yet often overlooked, is the need for effective preservice STEM teaching instruction for incoming educators. At a basic level, preservice STEM teacher education should include STEM content, pedagogy, and conceptualization. However, the literature suggests no leading conception of STEM education, and little is known about how preservice STEM teachers are conceptualizing STEM education. In order to explore preservice STEM teacher conceptions of STEM education, preservice teachers at a large, Midwestern research university were given an open-ended survey eliciting both textual and visual responses. Here, we report and discuss the results of employing this instrument in relation with the current STEM conceptualization literature.