The purpose of this study was to examine whether or not listening to music promotes falling asleep. Twenty university students, who usually listen to music at bedtime, were asked to take a nap in the laboratory while being monitored by a polysomnograph. Each participant selected preferred music to be played as they fell asleep. Stage 2 sleep latency was shorter for those sleeping with music playing compared to the no music control group. This tendency was reversed when participants tried to fall asleep quickly. Differences in sleep latency between the music and control conditions were due to the amount of episodic wakefulness. Results imply that music promotes or interferes with falling asleep by modulating the appearance of episodic wakefulness. Considering the mood, especially pleasantness while falling asleep and the ironic process theory of mental control (Wegner, 1994), the mechanisms of the effects of music on sleep are discussed. There is a possibility that listening to music promotes falling asleep though this may only be effective after balancing other factors.