A new line of research suggests that the personality trait of neuroticism may incline young people to use maladaptive musical emotion regulation strategies that in turn mediate an increase in their internalizing symptoms. However, it is unknown if this pattern is similar depending on how much music training young people have received in their lifetime. Therefore, the primary objective of this study was to examine four moderated mediation models in which music training (years of private lessons) may moderate how four maladaptive musical emotion regulation strategies (rumination, discharging negative emotions, avoidant coping, and liking sad music), respectively, mediate the relationship between neuroticism and internalizing symptoms (depression and anxiety). The sample comprised 647 university students aged between 17 and 21 years and ranging from not being a musician to having extensive music training. General (nonmusical) emotion regulation and coping strategies were statistically controlled to isolate potential effects inherent to music listening. Results indicated that liking sad music mediated the link between neuroticism and internalizing symptoms but that this mediation effect was not significant in music listeners who had cumulated more music training throughout their life. In this case, perhaps extensive music training was a protective factor against maladaptive musical emotion regulation. Nevertheless, across a variety of musicianship characteristics, musical emotion regulation strategies showed more similarities than differences between musicians and nonmusicians. In sum, among four musical emotion regulation mechanisms, liking sad music might be a more consistent emotional pathway from neuroticism to internalizing symptoms in young music listeners with less music training.