Objective To explore the effect of the clinical scenario-based simulation communication education based on Calgary -Cambridge Guide for undergraduate nursing students. Methods Totally 87 undergraduate nursing students were enrolled and divided into the experimental group (n=44) and the control group (n=43). The experimental group received clinical scenario-based simulation communication education based on Calgary -Cambridge Guide for communication. The control group received traditional class-based education for communication. The clinical communication skills questionnaire and Communication Observing Questionnaire were administered before and after the training. The testing results of both groups were compared. Results After participating in the education project, six dimensions of clinical communication competence and the total score were significantly improved after training compared with those before training in the experimental group. After training, the experimental group was better than the control group in establishment of harmonious relationship, confirming patients' problems, efficient information transfer, validation experience and communication competence,t values were 2.64, 2.32, 2.19, 2.20 and 4.36,P< 0.05. In testing of integrated cases, scores of six aspects such as case design, information collection, explaining behavior, relationship development, conflict coordination and service behavior in the experimental group were significantly higher than those of the control group,t values were 2.15, 2.10, 3.26, 2.84, 2.14 and 2.61,P<0.05. Conclusions The clinical scenario -based simulation education based on the Calgary-Cambridge Guide can improve communication competence of nursing students. Key words: Teaching; Students, nursing; Communication; Scenario-based simulation