The purposes of this longitudinal study were to (1) explore the stressors and coping behaviors of mothers having a child with congenital heart disease undergoing open heart surgery, and (2) understand the changes over time in these stressors and coping behaviors as the treatment process progressed. The field method was used to collect data, which was transcribed as a narrative verbal process recording. The records were then analyzed by content analysis. This study had ten subjects chosen by purposive sampling. The results showed that stressors on the mother whose child was undergoing open heart surgery could be inductively categorized as follows: the ill child, the treatment, and the mother herself. The coping behaviors consisted of cognitive beha-vior, emotional response, and management. At different stages of the 5045 behavior units were coded. There was a significant difference in the contribution of the stressors and coping behaviors at different stages of the treatment process. The findings can help nurses better understand the experience and provide some directions to assist mothers with child undergoing open heart surgery.