The objective of this study was to adapt the Teaching Engineering Self-Efficacy Scale (TESS) to Turkish through comprehensive validity and reliability assessments and to analyze science teachers' (specializing in science, physics, chemistry, biology) Teaching Engineering Self-Efficacy (TES) beliefs concerning various variables. The study employed the TESS, originally developed by Yoon, Evans, and Strobel (2014), alongside a personal information form, and followed a descriptive survey model as its research methodology. The adapted TESS's validity and reliability were evaluated using data from 476 science teachers in schools under the Ministry of National Education (MoNE) in X province, and the main study involved 221 science teachers from Y province. The assessment of teachers' TES beliefs in relation to different factors was executed using independent samples t-tests, One-Way ANOVA, and the Scheffe test. It revealed that science teachers' TES beliefs significantly varied based on factors such as their involvement in providing engineering education, the integration of engineering education into their teaching, and their specific teaching subjects, but not gender. The study contributes a valid and reliable scale to the academic literature.