A community of practice is an important mechanism to integrate participants' learning and knowledge. However, little research has discussed the concept of shared repertoire within a community of practice, to say nothing of looking at this concept from the angle of older adults' learning. In order to close the gap, this article tried to indicate key elements of forming a shared repertoire within the context of older adults' communities of practice. The researchers explored older adults' interactions within Chinese music groups in Taiwan by using qualitative approaches, including the semi-structured interview method and the observation method. Five Chinese music groups in the southern Taiwan area were visited, while a total of 20 interviewees were recruited. The researchers interviewed four persons in each musical group, namely the leader, two old-timers and a newcomer. The findings supported Wenger's arguments about shared repertoire and contribute to gerontology education. The arguments highlighted the importance of leadership and shed light on the relationship between particular structured and unstructured learning behaviors. Some keys about facilitating older adults' communities of practice were also identified in this research.