Background <p>Direct current shock interventions, including defibrillation and synchronized cardioversion, are critical lifesaving procedures in emergency departments and intensive care units. Nurses play a central role in preparing, monitoring, and in many clinical contexts initiating direct current shock therapy; however, concerns persist regarding variability in nurses’ knowledge and practical skills, which may compromise patient safety.</p> Aim <p>This systematic review aimed to synthesize evidence on nurses’ baseline knowledge and practical skills related to direct current shock management and to examine the effects of educational interventions on these competencies.</p> Methods <p>A systematic review was conducted in accordance with PRISMA guidelines and prospectively registered with PROSPERO. Searches were performed in Web of Science, Scopus, PubMed, ScienceDirect, and the Cochrane Library from 2010 to 15 March 2025. Quantitative and mixed-methods studies assessing nurses’ knowledge and/or skills related to defibrillation or cardioversion were included. Study selection, data extraction, and quality appraisal using the Critical Appraisal Skills Programme (CASP) checklists were undertaken independently by two reviewers. Given variations in study designs, outcome measures, and assessment tools, findings were synthesized narratively.</p> Results <p>Seven studies met the inclusion criteria, encompassing cross-sectional, quasi-experimental, and randomized controlled designs. Baseline assessments frequently demonstrated low to moderate levels of nurses’ knowledge and skills, particularly in rhythm recognition, energy selection, safety precautions, and post-shock care. Three studies evaluating educational interventions reported short-term improvements in knowledge and/or practical performance. However, follow-up durations were limited, outcome measures varied, and methodological limitations were common. Overall methodological quality ranged from low to high.</p> Conclusion <p>Available evidence suggests the presence of gaps in nurses’ baseline knowledge and skills related to direct current shock management. Educational and simulation-based interventions were associated with short-term improvements, although the strength of evidence remains limited due to the small number of heterogeneous studies. Further nurse-focused, methodologically robust research with standardized outcome measures and longer follow-up is required.</p> Clinical trial number <p>Not applicable.</p> Registration <p>Systematic review was conducted following PRISMA guidelines and prospectively registered with PROSPERO (CRD420251172168).</p>