Electronic Theory of Organic Chemistry is one of the most characteristic theories in chemistry. This theory continues to be taught in current chemical education, despite its incompatibility with quantum theory and its clearly recognized limitations. How can this be explained? I will try to answer this question using the concept of explanatory understanding, which has recently been discussed in the philosophy of science. In doing so, I intend to use De Regt's approach (2017) to scientific understanding as a kind of explanatory understanding. By looking at it from the perspective of scientific understanding, I will be able to defend electronic theory of organic chemistry in this sense, as it provides organic chemists with an understanding of the phenomenon of organic synthesis.