Objectives This pilot randomized controlled experimental study was conducted to investigate effects of music on sleep quality and comfort levels of pregnant women. Methods The sample of the study consisted of 70 pregnant women who met the inclusion criteria and agreed to participate in the study. The pregnant women were assigned to the music (n=35) and control groups (n=35). In the study, the musical pieces composed in Ussak mode were played for the participants in the music group. The pregnant women in the music group were first asked to empty their bladder and then listen to music for 30 min in a semi-Fowler's position with their head and shoulders raised 30 degrees, in a quiet and dim environment, every other day for two weeks before going to sleep. The Pregnant Information Form, Prenatal Comfort Scale (PCS) and Pittsburgh Sleep Quality Index - 1 week (PSQI-1 week) were used to collect the study data. Results The analysis of the mean scores obtained from the overall PSQI-1 week by the pregnant women in the music and control groups by weeks demonstrated that there was a statistically significant difference between the music and control groups in the second week (p<0.05). There was no statistically significant difference between the two groups in terms of the mean scores they obtained from the overall PCS (p>0.05). Conclusions Music increased the sleep quality of the pregnant women in the music group, but had no effect on their comfort levels.