The present invention provides a MIDI playing method comprising the steps of when synchronous event messages embedded in MIDI data are detected on the sequencer side which analyzes MIDI data in order along a time series of the MIDI data where the MIDI data are analyzed from the head of music to carry out MIDI musical performance, accumulating the number of the synchronous event messages and requesting a host CPU to make interrupt processing; and executing synchronous event processing on the host CPU side having received the request for the interrupt processing therein until the number of executed synchronous events and the accumulated value coincide with each other.