This study presents a research on the use of nanofluids in solar thermal systems. The aim of this study is to investigate the potential benefits of using nanofluids, such as increased efficiency and reduced costs. Nanofluids are a type of fluids that contain nanoparticles capable of enhancing thermal properties. The thermal efficiency of systems using nanofluids has been observed to be higher compared to systems using water as the working fluid. In this study, solar thermal energy and systems, nanofluids and their structures, integration of nanofluids into solar thermal systems, and the positive and negative effects of nanofluid usage in these systems were examined, highlighting the necessity of their integration. Furthermore, the study demonstrates that the use of nanofluids can reduce the size of the solar collector required to achieve the same performance level, which can lead to a decrease in the overall cost of the solar thermal system. The results of this study indicate that the use of nanofluids in solar thermal systems can significantly enhance efficiency and reduce costs. However, further research is needed to fully explore the benefits and limitations of using nanofluids in solar thermal systems