AIM: This study systematically analyzes key factors influencing nurses' genetic nursing competency to inform future genetic nursing education, research and practical interventions. BACKGROUND: The advancements in genomic technology, genetic nursing has emerged as a critical component of personalized and precision medicine. However, existing research suggests that many nurses lack adequate preparation to address genetic nursing competency effectively. DESIGN: This systematic review was registered in the International Prospective Register of Systematic Reviews (CRD42024577323) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. METHOD: This systematic review retrieved quantitative studies published between January 2009 and June 2024 from seven databases. The inclusion process involved initial screening, full-text assessment for inclusion criteria and methodological assessment. Two researchers independently conducted literature screening and quality assessment using Zotero software, with discrepancies resolved through discussion or consultation with a third researcher. Thirteen studies included, encompassing 6816 registered nurses from multiple countries. The Joanna Briggs Institute risk of bias criteria was used for quality assessment and traditional content analysis was used to summarize quantitative findings. RESULTS: Thirteen factors influencing genetic nursing competency were identified across three levels: individual (education, gender, work experience, basic knowledge, professional attitude, clinical skills, self-confidence, genetic awareness), environmental (unit differences, cultural and ethical cognition) and organizational (professional roles, professional development, leadership support). DISCUSSION AND CONCLUSION: This study highlights individual, environmental and organizational factors affecting nurses' genetic nursing competencies. It emphasizes the need for targeted training, leadership support, policy development and international collaboration to achieve these competencies globally.