Method and apparatus for designating performing notes based on synchronization information are provided. After detecting meta score information from a musical score or MIDI (Musical Instrument Digital Interface) data to be performed, note position information for all notes included in an electronic score is generated based on the musical score or the meta score information. By utilizing the note position information and synchronization information, which includes the sync performance time at which each note is to start to be performed, performing notes are designated on the electronic score at each time synchronized. The synchronization information may be generated from the meta score information or the MIDI data, or may be read from a synchronization information file stored in advance. Alternatively, the synchronization information may be generated in real time by analyzing live input sound.