The rolling-over of the body is one of the developmental mile-stones. Several infants have the laterality of rolling-over in early state and the dominant side in later state. The abilateral occipital flattening is thought to be caused by head positioning in the neonatal period and early infancy. Asymmetrical development of rolling-over was studied in relation with head positioning, relating skull occipital flattening. We examined 2919 infants aged 7 months with the questionnaire about the side of skull occipital flattening and the initial turning side of rolling-over. 1975 infants had the dominant side of rolling-over; the left side 45.4%, and the right side 47.7%. 761 infants had one-sided occipital flattening; left-side 41.3%, and right-side 54.8%, 520 infants had dominant-sided rolling-over accompanied with one-sided occipital flattening. The positive relationship between the side of rolling-over and the side of occipital flattening could not be proved by chi-square statistical analysis. These findings suggest that laterality of rolling-over, one of asymmetrical motor developments is not related to the head positioning in early infancy.