ObjectiveTo evaluate engagement with and efficacy of guided versus non‐guided digital interventions targeting psychological symptoms of cancer via a systematic review of current evidence.MethodsPubMed, Scopus, PsychINFO, MEDLINE, and CINAHL databases were searched. Eligible publications were randomised controlled trials of guided or non‐guided digital psychological interventions used in cancer settings reporting intervention efficacy and/or engagement. Study methodological quality was assessed using the Cochrane risk of bias (RoB) tool. Random effects meta‐analyses were performed on outcomes with sufficient data, with sub‐group analyses of intervention type and follow‐up period.ResultsForty‐three studies were included. Studies varied by level of guidance, type of technology used, duration, and outcomes assessed. Most studies had a high overall RoB. Meta‐analysis indicated that guided interventions significantly reduced distress, anxiety, and fatigue, while non‐guided did not. For depression and quality of life, both guided and non‐guided interventions produced significant improvements. Guided interventions reported higher levels of intervention engagement than non‐guided.ConclusionsGuided digital psychological interventions were likely to be more effective than non‐guided ones for cancer patients, particularly in reducing distress, anxiety, and fatigue. Whilst both types were found to improve depression and life quality, guided interventions were associated with higher patient engagement. These findings suggest digital interventions could supplement traditional cancer care, warranting further research concerning long‐term effects and cost‐efficiency.