[目的]了解海南省儿童精神障碍患者的苯丙氨酸浓度。[方法]对1169例精神异常的儿童进行苯丙氨酸浓度测定。[结果]1169例儿童精神障碍患儿中高苯丙氨酸血症有156例、PKU患儿5例;占全部患儿的13.77%。[结论]儿童精神障碍患者苯丙氨酸浓度的升高应引起精神科医生的高度重视,血中苯丙氨酸浓度可做为儿童精神障碍患者筛查的一个生物指标。 [Objective] To understand the phenylalanine concentration in children with mental disorders in Hainan Province. [Method] A total of 1169 children with mental disorders were tested for phenylalanine concentration. [Results] 156 cases of hyperphenylalaninemia and 5 cases of PKU were found in 1,169 children with mental disorders, accounting for 13.77% of all children. [Conclusion] The increase of phenylalanine concentration in children with mental disorders should be paid great attention by psychiatrists. The concentration of phenylalanine in blood can be used as a biological index for the screening of children with mental disorders.