Abstract: In a musical performance support system including a sensor device that is attached to a musical instrument and an operation device that is able to perform wireless communication mutually with the sensor device and is able to perform communication with an instructor terminal of an instructor via a server, the sensor device transmits a detection signal detected by an acceleration sensor that has at least to detection axes to the operation device, the operation device generates practice result information of musical performance of a user using the musical instrument and transmits the practice result information to the server, and the operation device receives guidance information in response to the practice result information from the instructor terminal through the server and causes display means to display the guidance information.