School-based agricultural education programs are recognized as contributors to teaching contextualized mathematics and supporting STEM education. This study examined the mathematics teaching efficacy and professional development needs of Tennessee school-based agricultural education teachers related to teaching contextualized mathematics. Tennessee agricultural education teachers were moderately efficacious in Personal Mathematics Teaching Efficacy and Mathematics Teaching Outcome Expectancy, and this may negatively impact the teaching of mathematical concepts found in Tennessee's agricultural education curricula. Also, similarities and differences were found in the teachers' professional development needs based upon mathematics teaching efficacy. Future research should seek to discover factors impacting the development of mathematics teaching efficacy among school-based agricultural education teachers. We also recommend professional development related to teaching contextualized mathematics be tailored to the different needs of teachers by states or regions.