Objective To evaluate the physical and neuropsychological development of children with dietation-treated phenylketonuria (PKU). Methods A total of 41 PKU children with phenylalanine hydroxylase deficiency in Wuxi city from January 2004 to December 2014 were enrolled. Height (length),weight and neuropsychological development scale for children aged 0-6 years were monitored,and phenylalanine dietary control index was calculated. Results 1)The blood phenylalanine concentration of PKU children decreased significantly before and after treatment,with an average decrease(506.57±40.54) μmol/L,which was statistical significance (H=21.232, P＜0.05).2)Among children aged 6 months,1 year,2 years and 3 years,the medium level height and weight accounted for the most,the height accounted for 70.7%,65.9%,68.3% and 68.3%,respectively,and the medium weight accounted for 78.0%,73.2%,75.6% and 73.2%,respectively.3)There were no significant differences on the physical and neuropsychological between children of different ages and types of PKU(P>0.05).4)The level of neuropsychological development was negatively correlated with the diagnosis and treatment time,blood phenylalanine concentration and dietary control index of PKU children (r=-0.601,-0.838,-0.792,P <0.05). Conclusion PKU children treated with diet and standardized follow-up can maintain normal physical and neuropsychological development levels,which are affected by the time of diagnosis and treatment and the concentration of phenylalanine in blood.