Purpose: This study was to develop a nursing education program for mothers with a young child undergoing cardiac surgery and determine effects of the program on her knowledge, anxiety and coping behavior. Methods: The research design was a nonequivalent control group non-synchronized design. 18 mothers were assigned to the experimental group and 18 to the control group. The effects were evaluated by measuring knowledge, anxiety, and coping behavior. The collected data was analyzed through independent t-test, and repeated measures ANOVA respectively using SPSS/WIN 12.0 program. Results: The point of knowledge in the experimental group was significantly increased tan that in the control group. The point of subjective, physiological, and behavior anxiety in the experimental group was significantly decreased than that in the control group by time change. The point of coping behavior in the experimental group was significantly higher than that in the control group. Conclusion: The nursing educational program for a young child with cardiac surgery is expected to be clinically applied as an intervention program for mothers with a young child undergoing cardiac surgery.