This article focuses on STEM integration as an important aspect of applying this approach in education. It presents the author's concept of its planning and implementation on the basis of systems theory and the systems approach. In this context, the components of STEM education are viewed as a system that emerges and operates "under the influence" of the so-called "system-generating factor." This leads to the distinction of two types of STEM integration: knowledge-based and skill-based, each defined as a primary component of the system-generating factor. The research methodology involves the conceptualization of this idea through literature review, definition, and critical analysis. The main goal of the literature review is the investigation of theoretical sources concerning different models of STEM integration and those that focus on the application of the systems approach in education. The main concepts in the proposed model are defined. The critical analysis of the author's model refers to discussing the opportunities for implementation in real pedagogical practices, its strengths and weaknesses, and also the potential opportunities for future scientific research.