The purpose of this study is to develop a practice record visualization system using a piano performance tracking technology that utilizes gaze information. In general, piano lessons are held regularly, e.g., once a week, and the teacher observes the student’s skills at a fixed point. However, it can be difficult for the teacher to fully understand and address all areas how the student has practiced from the previous lesson to the current lesson and need improvement. This makes it difficult to provide appropriate guidance in lessons, such as determining whether students are too nervous to perform well in front of the teacher, or whether they are also unable to perform well in home practice. To solve this problem, we propose a performance tracking algorithm that can handle keystroke errors and replaying, and a system that visualizes the amount of practice and other practice progress. The proposed system visualizes the amount of practice and errors in various units, such as notes and measures. To verify the usefulness of the proposed system, we conducted an evaluation experiment comparing the case of using the proposed system and not using the proposed system.