[Purpose] In this study, we quantitatively evaluated how the positioning program influenced the movement patterns of preterm infants in the neonatal intensive care unit (NICU). [Subjects and Methods] Spontaneous movements of 12 low-risk preterm infants were video-recorded at 38 or 39 postmenstrual weeks of age (PMA). Six of them (positioning group) received a positioning program from birth to 35-36 weeks of PMA while the other 6 (non-positioning group) did not. We attached reflective markers on the infant's wrists and ankles in the supine position and filmed them from above. By using a two-dimensional image analysis system, we digitized the wrist and ankle trajectories and analyzed the data by calculating several statistics. [Results] Infants in the positioning group brought their hands to the midline or crossed their hands over the midline and showed more variation in velocity of movements than those in the non-positioning group. We also noticed that infants in the positioning group exhibited and maintained a movement pattern similar to that of full-term infants at 1 month after the positioning program was terminated. [Conclusions] These results suggest that appropriate positioning of preterm infants facilitates flexion posture and movement patterns toward the centre of the body similar to foetuses in the uterus.