This study aimed to develop conceptual frameworks on how to teach STEM concepts in a Bahasa Indonesia subject as integrated learning. This study used a mixed-methods research design that consisted of a document analysis, a survey, and a systematic review. To address the aims of this study, we first determined the STEM concepts on basic competencies of a Bahasa Indonesia subject of Grades 1–3 at elementary school level in the curriculum 2013; the recommended teaching and learning strategies in learning STEM concepts integrated into a Bahasa Indonesia subject of Grades 1–3 at elementary school in the curriculum 2013; and the first proposed conceptual frameworks on how to teach STEM concepts in a Bahasa Indonesia subject as an integrated learning in Grades 1–3 at elementary school level in the curriculum 2013 based on systematic review. The results showed that the conceptual frameworks on how to teach science concepts in a Bahasa Indonesia subject as integrated learning in Grades 1–3 at elementary school level in the curriculum 2013 consisted of Bahasa Indonesia as the main goal and science concepts as an approach to address goals, and recommends it be taught using reading. The conceptual framework on how to teach technology concepts in a Bahasa Indonesia subject as an integrated learning in Grades 1–3 at elementary school level in the curriculum 2013 consisted of Bahasa Indonesia as the main goal and technology concepts as an approach to address goals, and recommends that it be taught using reading. These findings will be useful to Indonesian teachers and teachers in other countries that have integrated science or STEM concepts in the language subject in their curricula as integrated learning or will use integrated learning in their future curricula to contribute to sustainability education.