Objective To investigate the application of bedside ultrasound in evaluating the development of early neonatal spinal cord and spinal canal. Methods Clinical data of 125 newborns in the Second Hospital of Lanzhou University from January 2022 to August 2022 were collected, including maternal delivery times, delivery methods, gestational age, sex, days of birth, height, weight, head circumference and chest circumference. The cervical, thoracic, lumbar spinal cord and anterior and posterior diameter of spinal canal were measured by bedside ultrasound. According to their gestational age, they were divided into preterm infants group (32~36+6 weeks, 30 cases), early term infants group (37~38+6 weeks, 39 cases) and full term infants group (39~40+6 weeks, 56 cases). The difference of spinal cord and spinal canal diameter between groups and its correlation with clinical data were compared, and the regularity of spinal cord and spinal canal diameter with gestational age was further observed.〖WTHZ〗Results The anteroposterior diameters of the spinal cord and spinal canal in full term infants group and early term infants group were higher than that in the preterm infants group(P<0.05). The anteroposterior diameters of early neonatal spinal cord and spinal canal were positively associated with gestational age, height, weight, head circumference and chest circumference, especially were significantly associated with gestational age in the preterm infants group (P<0.05). No gender differences were found in the development of the spinal cord and spinal canal. Conclusion Bedside ultrasound can show the anteroposterior diameters of spinal cord and spinal canal varies with gestational age, the utility of reference values for spinal cord anteroposterior diameter in newborns is in the assessment of spinal cord injury