Introduction and significance of the study: Attention-deficit hyperactivity disorder is one of the most common behavioral and psychiatric disorders among children characterized by core symptoms of inattention, hyperactivity, impulsivity, easy distraction from important tasks, mood swings. Mothers of children with ADHD have reported higher levels of stress, lower levels of quality of life, and lower maternal satisfaction which increases the child's perplexing behavior that elicits harsh motherhood. Therefore, mothers play a unique role in ADHD child’s management as the primary caregivers for their children, therefore, mother training is one means through which social and psychological help can be provided and to improve their caregiving behaviors using the intervention guidelines in order to increase positive outcomes in their children's care and treatment. Aim: This study aimed to evaluate the effectiveness of intervention guidelines on mothers of children with attention deficit hyperactivity disorders. Subjects and Methods: Research design: A quasi-experimental research design with pre-post assessment for one group was used in this study. Setting: This study was conducted at the child psychiatric outpatient clinics at El-Fayoum and Zagazig University Hospital and Child Clinic of EL-Abbassia Governmental Hospital, El-Tarbya El-Fekrya Schools and Development Referral Centers at El-Fayoum City as Sondos Academy Centers, Ibny and Together Centers. Subjects: This study was carried out on 150 mothers and their children who have been diagnosed with ADHD. Data collection Tools: Data were collected using three tools:(I) A structured interviewing sheet. (II) Mothers' knowledge questionnaire to assess studied mothers' knowledge about ADHD in their children (pre, post, and at one-month follow-up) and (III) A self-reported practices guideline (pre/post and at one-month follow-up tests) to evaluate studied mothers' reported practices. Results: 62% of the studied children's age, ranged from 6-12 years, 74% of children were males and 78%of them were in schools. As regards the order of birth, 60% of children were the first order in birth and half of them had a mild degree of ADHD. Also, the duration of disease was two years in more than half of children (65%). Majority of mothers (90%) had an unsatisfactory level of knowledge before the implementation of the intervention guidelines, which improved for 88% immediately after the intervention guidelines. Also, it showed that, 80% of the studied mothers had a satisfactory level in their total knowledge scores in the follow-up phase of intervention guidelines, with highly statistically significant differences. As well as a highly statistically significant positive correlation between knowledge scores, practice scores with mothers' age and educational level at the post and follows up phases of intervention guidelines implementation (P<0.001). Conclusion: Based on the results of the present study, it can be concluded that, there were highly statistically significant improvements in mothers' knowledge and reported practice immediately post and at following-up of intervention guidelines implementation. Moreover, there were significant positive correlations between mothers' knowledge, practices, age, and level of education at pre, immediately post and at follow-up of intervention guidelines implementation. Recommendations: The study recommended continuous training for mothers having children with ADHD. Also, further studies will be needed to evaluate the effect of intervention guidelines on the mothers’ coping, quality of life (QOL), mothering satisfaction, psychological well-being to enhance their knowledge, attitudes, and practices in improving their children’s outcomes.