The purpose of this study was to examine the teachers` perception and practice of lullaby music utilized in the nap time in child care centers and to find out the characteristics of preferred lullaby music so as to suggest effective utilization of good nap time music for young children, which might help children`s musical, physical and emotional development as suggested by the National curriculum for young children. Survey questionnaire was conducted with 120 teachers in the child care centers in B metro city and the characteristics of highly preferred lullaby music was analysed according to the cultural background and musical characteristics. From this study, it was found that music was necessary in nap time and the lullaby music as an effective means to facilitate nap and that the most widely used medium was CD. From the 73 collected song datum, it was found that the largest number of the songs were Western music such as a lullaby by Brahms and the most dominant form of performance was instrumental works. Major musical characteristics of favorite 20 songs were in C major, four-four meter, aa`a repetitive form and in slow tempo of andante.