We analyzed the processes of making aesthetic judgments of music, focusing on the differences between music experts and laypersons. Sixteen students of musicology and 16 control subjects (also students) judged the aesthetic value as well as the harmonic correctness of chord sequences. Event-related potential (ERP) data indicate differences between experts and laypersons in making aesthetic judgments at three different processing stages. Additionally, effects of expertise on ERP components that have previously been proven to be sensitive to musical training were replicated. The study thus provides insights into the effects of musical expertise on neural correlates of aesthetic music processing.