Objective To discuss the effect of virtual simulation based lab teaching on maternal-infant care core competencies of nursing undergraduates. Methods A lottery method was used to randomize 120 nursing undergraduate students into 2 groups of 60 each.The control group was subjected to case demonstration based lab teaching, while the to case demonstration combined with virtual simulation based lab teaching. The classroom learning effect, examination results, and maternal-infant care core competencies levels were evaluated and compared between the 2 groups. Results After lab teaching, total and dimension (knowledge and expertise, speciaty-oriented skills, clinical thinking and flexible response) scores of maternal-infant care core competencies in the intervention group were significantly higher than those in the control group （P＜0.01 for all）, with the intervention group having better classroom learning effect, and higher examination results, than the control group （P＜0.01 for both）. Conclusion Adding virtual simulation based teaching into case demonstration in lab teaching of obstetric nursing skills can significantly improve nursing undergraduates′ learning effect of maternal-infant care teaching.