Background: Holistic nursing care including spiritual care should be provided to critically ill patients. Critical care nurses should assess the patients' spiritual needs and provide holistic nursing care accordingly. Nurses' spiritual perception and competency may be facilitators or barriers to the spiritual practice of critical care nurses. So, the current study was conducted to assess this relationship. Objective: To assess critical care nurses' spiritual care practice and its relationship with their spiritual perception and competency. Design of the study: A descriptive correlational research design. Settings: Seven intensive care units at the Alexandria Main University Hospital. Subjects: A convenient sample of 150 critical care nurses who provide direct care to patients were enrolled in the study. Tools: Three tools were used in this study. Tool one was the spiritual care practice questionnaire. Tool two was the spirituality and spiritual care rating scale, and tool three was the spiritual care competency scale. Method: Online questionnaire was sent to critical care nurses to report their spiritual care practice, perception, and competency. Results: Critical care nurses' spiritual care practice was positively and significantly correlated with nurses' perception of spiritual care (r=0.55, P= 0.04), and awareness of spiritual care competency (r=0.87, P= 0.02). Conclusion: Critical care nurses provide spiritual care when they have a positive attitude toward spiritual care and are aware of spiritual care competency components. Recommendations: Raise critical care nurses' awareness of spiritual care competency to provide a more positive attitude toward spiritual care and provide satisfactory spiritual care to critically ill patients.