The piano is a western musical instrument. The art of piano performance has made great progress in China. Education is essential for the inheritance and development of the arts, including the piano. Piano lessons play an important role in music education and are the foundation of music education. Teachers play a leading role in the learning process. The comprehensive quality of teachers, including ideological and moral accomplishment, cultural accomplishment, work level, teaching theory, and artistic aesthetic level, directly or indirectly affects the teaching level and the growth, learning, attitude, and concept of students. Through the research and experiment on the application of composite nanomaterials in the teaching of piano touch and timbre expressiveness, the experimental data showed that after the improvement of piano touch and timbre performance by nanomaterials, the students’ interest in the piano improvisational accompaniment course has greatly increased. There were 86 people who were interested, accounting for 86.13%. There were 13 people who were not interested and indifferent, accounting for 13.87%. Compared with the increase of 36 people who were interested before the improvement, the number of people, who were not interested and indifferent, was decreased by 36 people. From the abovementioned data, it can be seen that the application of nanomaterials in piano teaching, it has made an indispensable contribution to the development of piano teaching.