At present, the field of piano teaching is facing challenges such as excessive reliance on teachers' subjective experience and lack of real-time feedback from students' performance. In addition, incorrect hand posture during piano performance can also easily lead to occupational injuries. With the development and popularization of machine learning models, computer vision technology, and multimodal sensors, artificial intelligence and machine learning technology are driving a paradigm shift in piano teaching. In this study, an intelligent piano education model based on Convolutional Neural Network (CNN) was designed to address the issues of hand posture recognition and rhythm structure analysis during student piano performance. Firstly, based on the hand images collected during the student's performance, key nodes of the hand are identified, and combined with biomechanical models, health indicators such as wrist collapse angle are quantitatively evaluated. In addition, based on the recorded information of students' performances, the short-term energy, zero crossing rate, and Mel frequency spectrum characteristics of the recorded data are integrated to accurately analyze the rhythm structure of students' performances using a CNN model. This study reveals the impact of abnormal hand postures on rhythmic fluctuations, while also validating the application effectiveness of CNN in piano performance hand posture recognition and rhythm structure analysis.