The purposes of this study were to explore the level and sourses of uncertainty and hope in pre- and post-cardiac surgical patients, and to examine the correlates of uncertainty and hope. Twenty-five subjects were recruited by convenience sampling from two medical centers and one regional hospital in southern area of Taiwan. Instruments were Chinese Version of Mishel Uncertainty in Illness Scale and Chinese Version of Herth Hope Index. The results of this study showed that: (1)the level of uncertainty was moderate before surgery but decrease to lower level after the surgery. The major sourses of uncertainty is ambiguity related to illness. (2)the level of hope was both high during pre- and post-surgery. (3)age was negatively related to uncertainty, there was a positive relationship between hospitalization day and uncertainty in pre-surgery. Sex variable was significantly difference from uncertainty, and educational level revealed not Findings from this study suggested that although pre-cardiac surgery patients is in moderate state of uncertainty, individualized and diversified teaching program should be provided. Moreover, fostering and maintaining hope through cardiac surgery process is imperative. Its is hoped that this study will help nurses apply this knowledge to their clinical practice and facilite further studies on these clients.