The vietnam’s new general education curriculum is transferring from content orientation to students’ capacity and quality development orientation. Stem (is acronym words of science, technology, engineering, and mathematics) education contributes to the development of 21st century skills of students. In order to successfully implement stem education, in addition to leaders, managers and programmers, teachers have an important role in directly building and organizing stem education. And pre-service teachers need to be trained to deal with complexities of education. The purpose of this research is to assess the pre-service chemistry teachers? Existing stem teaching capacity in vietnam. Research method was survey through a set of unstructured and structured questions, and participants of this research are 57 pre-service chemistry teachers (who are 3rd and 4th grade learners of 5 universities of education representing all three regions of vietnam). Content analysis was used to analyze the data from unstructured questions while the data from structured questions were transformed into frequency, percentage and descriptive statistic analyze. The findings indicated that most of participants have conceptualized the aspects of stem in accordance with a number of researches in the world. However, they were less capable in designing their teaching stem and performing teaching stem in the classroom, beside assessment abilities were not good and lack diversity. They also suggested that there should be a specific guide material on how to design and conduct stem teaching. Therefore, the study also suggested measures to develop stem teaching competences for pre – service chemistry teachers in vietnam: 1) redesign the teacher training program to include stem educational modules, 2) provide stem teaching instruction modules from stem fields in chemistry, and 3) combine blended learning approach to enhance their ict ability. Published under licence by iop publishing ltd.