The importance of music teachers reflecting on their teaching practise has been discussed for a long time [(Gaunt 2008. "One-to-one Tuition in a Conservatoire: The Perceptions of Instrumental and Vocal Teachers." "Psychology of Music" 36 (2): 215-245; Schön 1987. "Educating the Reflective Practitioner." San Francisco)]. However, Haddon [(2009. "Instrumental and Vocal Teaching: How Do Music Students Learn to Teach?" "British Journal of Music Education" 26 (1): 57-70)] noticed that some private instrumental teachers simply relied on their previous learning and teaching experiences to teach. This qualitative study aimed to understand how private piano teachers reflected on their teaching in terms of their teaching challenges and their pupils' learning challenges. In reflecting on their own teaching, most of the participants focused mainly on analysis of pupils' playing errors, and they tended to believe that repeated practice by the learners was the best approach to improving performance. In contrast, a few participants believed their expertise in both music and teaching could help their learners to deal with learning difficulties. Based on the two different reflective attitudes, participants developed their teaching competence differently. These results imply that teachers' attitudes towards reflection mainly related to their assumptions about education.