Background Globally, one in 10 children live in regions affected by armed conflict. Children exposed to armed conflict are vulnerable to social and emotional difficulties, along with disrupted educational and occupational opportunities. Most armed conflicts occur in low‐ and middle‐income countries (LMICs), where mental health systems are limited and can be further weakened by the context of war. Research is needed to determine feasible and cost‐effective psychosocial interventions that can be delivered safely by available mental health workforces (including nonspecialists). A vital first step toward achieving this is to examine evidence‐based psychosocial interventions and identify the common therapeutic techniques being used across these treatments. Methods A systematic review of psychosocial interventions for conflict‐affected children and youth living in LMICs was performed. Studies were identified through database searches (PsycINFO, PubMed, Cochrane Central Register of Controlled Trials, PILOTS and Web of Science Core Collection), hand‐searching of reference lists, and contacting expert researchers. The PracticeWise coding system was used to distill the practice elements within clinical protocols. Results Twenty‐eight randomized controlled trials and controlled trials conducted in conflict‐affected settings, and 25 efficacious treatments were identified. Several practice elements were found across more than 50% of the intervention protocols of these treatments. These were access promotion, psychoeducation for children and parents, insight building, rapport building techniques, cognitive strategies, use of narratives, exposure techniques, and relapse prevention. Conclusions Identification of the common practice elements of effective interventions for conflict‐affected children and youth can inform essential future treatment development, implementation, and evaluation for this vulnerable population. To further advance the field, research should focus on identifying which of these elements are the active ingredients for clinical change, along with attention to costs of delivery, training, supervision and how to sustain quality implementation over time.