The aim of this study was to determine the effect of context-based learning approach on science and chemistry prospective teachers' understanding of nanotechnology. The study was carried out with prospective teachers of 4th grade science (21) and 4th grade chemistry (10). A quasi-experimental method was used in this study. As data collection tools, ‚Nanotechnology Test‛ and questionnaire were used. It is revealed that science and chemistry prospective teachers have equal prior knowledge about nanotechnology. In the post test, there was no significant difference between the prospective teachers' understanding of the subject. According to the data obtained from the test, it was concluded that the context-based learning approach used in the teaching of nanotechnology was effective for both groups. According to the results of the survey, it was found that the materials used in the study were interesting and useful in understanding the subject.