Importance and prevalence of STEM, which is a holistic educational approach that includes science, technology, engineering and mathematics, has been increasing in recent years. It is stated that STEM is very important for countries to compete and stand out in the new world order and economy. In this study, postgraduate theses on STEM education in Turkey were investigated by meta-synthesis method. In this context, 58 theses, 9 of which were doctoral and 49 of them were master's thesis were examined. Topics covered in the theses, research methods used, preferred sample groups, data collection tools and results presented in theses, similar and different aspects were examined in detail. It is understood that various skills, opinions, academic achievement, learning approaches, career, attitudes, and interest/perception are studied in the theses. In the studies, it was determined that mostly mixed, quantitative and qualitative methods were preferred respectively, middle school students and teacher candidates were frequently studied groups, and questionnaire/scale and interview (form) tools were frequently used as data collection tools. The results, similarities and differences of the theses were expressed with key statements and some suggestions were presented.