This study aimed to investigate the effects of learning songs by ear in multiple keys on memorization and sight-reading skills of music education undergraduates, and to examine their opinions on the method. The participants were 60 students from Erzincan University, assigned equally to experimental and control groups based on entrance exam scores. Using a mixed-methods design, quantitative data were collected through a quasi-experimental pre-test/post-test with control group, while qualitative data were obtained via semi-structured interviews. The treatment lasted eight weeks with one 30-minute session per week: the experimental group learned solfeggio pieces by ear in A major, D major, C minor, and G minor, while the control group continued with traditional notation-based ear training. Results revealed no significant difference between the groups, indicating that learning by ear is as effective as the traditional approach but does not provide additional benefits in developing sight-reading and memorization skills.