Objective:To investigate the effect and mechanism of passive smoking of pregnant rats on learning and memory of neonatal rats. Methods:Morris water maze which reflects learning and memory ability was used to test neurobehavioral changes in neonatal rats,and IRMA method was used to test nerve growth factor(NGF) content in cerebellar cortex of neonatal rats. Results:Passive smoking during pregnancy decreased the learning and memory ability in neonatal rats,meanwhile content of nerve growth factor in cerebellar cortex was significantly low. Conclusion:Reduced learning and memory ability in neonatal rats offspring by passive smoking of female rats during pregnancy correlates with reduced synthesis and secretion of nerve growth factor in cerebellar cortex.