Obsessive-compulsive disorder (OCD) is a severe mental disorder with serious consequences to family dynamics. Therefore, parental involvement seems to be a key factor for the successful treatment of this psychiatric disorder. The aim of this study was to evaluate the level of evidence available to allow recommendation of cognitive behavioral therapy (CBT) with family intervention for the treatment of children and adolescents with OCD. The systematic search was performed on MEDLINE/PubMed, followed by analysis of abstracts and full-length articles by two independent evaluators. Subsequently, an analysis of the evidence available was conducted using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The effect size of the intervention was calculated using Cohen’s d. We found 77 articles on PubMed, plus 12 articles via cross-reference search. Of these, seven articles were included in this review, according to the following criteria: intervention study, involving only children and/or adolescents, and a having a structured or clinical diagnosis of OCD. The Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS) was used for outcome evaluation in all articles, thus enabling assessment of the effect size of non-controlled interventions (d = 1.43), resulting in a mean difference of 13.11 points (95%CI 11.84-14.39; p < 0.001). Conversely, a high heterogeneity was detected among the studies (I² = 67%). Family-based CBT seems to have an important effect on the reduction of OCD symptoms in children and adolescents. However, the small number of studies available do not allow us to establish an evidence level higher than C for this recommendation. New randomized clinical trials are needed to confirm this recommendation.