The purpose of this study is evaluation the effect of parents education in verbal and non-verbal methods to control the amount of phenylalanine of the serum of children which suffering from phenylketonuria. The study population is 45 family and children which suffering from phenylketonuria with 1-18 years old in which referred to PKU clinic of Abuzar hospital. Inclusion criteria: Having a sick child that stricken to PKU; having a file at PKU clinic of Abuzar hospital; Pediatric patient ranging from 1 to 18 years old; The parents learning ability; Having the main care provider at home. Exclusion criteria: absence of parents for at least two training sessions. First, parents by completing questionnaires ,their knowledge about phenylketonuria ,in which has been finalized by professors of university of medical sciences, assessing their awareness of the phenylketonuria (PKU), and according to their scores, randomly they will be divided into two groups , intervention and control. The intervention group contains two group, 15 each, one group using verbal method within 8 sessions , 2 hours each, within one month; and the other group at the same period using non-verbal training method with booklet and pamphlets for one month and follow up, will be trained, The control group consisted of 15 member in which there is no intervention for this group. The Parents of both intervention and control groups after one month will fill up the knowledge questionnaires and their children phenylalanine level, before and after the intervention will be recorded.