Purpose: This study aims at determining the competencies of Korean nurses in prenatal genetic nursing. Methods: First, a 3-round Delphi survey was conducted to establish prenatal genetic nursing competencies. Second, a prenatal genetic nursing education program (PGNEP), incorporating the findings from the Delphi survey, was designed. Third, a single group pre- and post-quasi-experimental study at a PGNEP workshop was conducted to assess the effectiveness of the integration of the competencies into the PGNEP with the measurements of knowledge about prenatal genetic testing and nursing (K-PGTN) and information needs about prenatal genetic testing and nursing (I-PGTN). Finally, the identified competencies were reexamined for their clarity. Results: Based on the Delphi survey 78 competency components were identified. The components were then classified under 10 categories, which were organized under 4 domains. The domain of “experiential genetic nursing knowledge” and the domain of “ethics and law” were ranked as the first and the second in significance. The quasi-experimental study showed that the mean scores in K-PGTN were significantly increased from 8.19±2.67 to 11.25±2.51 (P<0.001). The mean scores of “ethics and law” in I-PGTN decreased significantly (P=0.023). The headings of 4 categories and 2 domains were revised. Conclusion This study identified competencies for prenatal genetic nursing and nursing education in Korea. There is a need for nursing instructors and researchers to improve the competencies of nurses in the identified areas. Particular emphasis should be placed on experiential nursing knowledge and on ethics and law related to prenatal genetic nursing.