With increasing interest in the emotional responses to music, some studies are specifically looking into music’s regulatory function on emotion, known as “music emotion regulation (MER)”. The purpose of this study was to examine the concepts on the regulatory impact of music on emotion using a scoping review procedure. Through an electronic database and manual searches based on the guidelines suggested by the JBI Manual for Evidence Synthesis, a total of 47 studies were identified and included for analysis. The results showed that there were some definitional challenges in each component of music emotion regulation. Most studies treated music as a single variable without exploring the regulatory mechanism of the intra-musical elements that constitute music. When examining the regulatory impact of music on emotion, emotion was inclusive of other terms ranging from feeling to mood. Most of the MER studies employed the terms used in the emotion regulation strategies; however, there were some regulatory processes that pertained solely to music’s cathartic effect. Overall, the results showed that music emotion regulation (MER) was not clearly distinguished from music emotion (ME) studies. Future research should allocate more attention to the theoretical mechanism behind music’s intrinsic regulatory effect in emotion regulation (MER) studies.