Ecological crises have affected the architecture discipline, and different techniques, technologies, and design approaches have flourished. A theory about the effect of ecology on architectural design, formulated as ecological design, and its education has started in institutes. However, it is important that the practice of architecture is reflected through theoretical knowledge in its outputs, and the discipline is conscious about its theoretical knowledge when designing a building, including how much can be understood in the concrete project. This study tries to discern the role of theoretical knowledge in practice and in final projects in the context of ecological design by estimating masters students' experiences, perceptions, and attitudes. The research method of this study is a qualitative approach, and in-depth interviews have been done with masters-level students. The results of this study showed that the theoretical knowledge given in the lectures could change the opinions of a designer regarding ecological design. Based on the results, ecological design courses can increase the popularity of ecological building design strategies, which offers potential for more sustainable living environments and more environmentally friendly buildings, and their spread into human environments.