Effective communication between nurses and physicians is necessary for prompt and accurate responses in clinical deterioration. This study aimed to examine nurses' perception and performance of communication with physicians in clinical deterioration situations in the ward. A descriptive research design with a survey of 250 ward nurses working in 2 tertiary hospitals was used. Regarding communication with the physician, nurses' perception was highest for timeliness, followed by accuracy, understanding, satisfaction, and openness, and their performance was highest for preparation, followed by situation, background, assessment, and recommendation. It is suggested that proactive activities for improving openness, accuracy, satisfaction, and mutual understanding between physicians and nurses are required for patient safety. Additionally, the performance for assessment and recommendations should be improved. Education programs for nurses and physicians should be developed and applied to clinical practice to promote understanding and trust in interprofessional communication.