It is inevitable that technology changes rapidly and individuals catch and learn this change. For this reason, technology-related training should and is given. These pieces of training start from the lowest level of education. It is important to meet, research, and practice technology, engineering, science, and mathematics (STEM) at all educational levels, starting from preschool. For this purpose, it is seen that STEM education is given in the preschool period. Preschool teachers play a key role in improving STEM skills. For this reason, the relationship between the teacher and the child is as important as the environment in learning. The teaching methods and techniques exhibited by teachers in STEM education cause children to increase their interest in scientific activities and to be willing to do scientific research. In this study, STEM education and STEM applications in preschool education were discussed.