Cardiac catheterization is the gold standard diagnostic test for coronary heart disease. The aim: the present study was conducted to assess the association between time of ambulation and clinical outcomes of patients after cardiac catheterization. Methodology: Setting: the study was conducted at the cardiac catheterization units at Ain Shams University Hospital and Ain Shams University Specialized Hospital. Design:The descriptive exploratory research design was utilized in this study. Subject: A purposive sample of 150 patients was used in the study. Tools: 1) Patients' interview questionnaire to assess patients' demographic characteristics data and patients' medical history. 2) Patient post cardiac catheterization clinical outcomes which included Vital signs: (temperature, blood pressure, respiration, pulse), O2 saturation, lower peripheral perfusion and cardiac catheterization site assessment. 3) Visual Analogue Pain Scale to assess pain intensity. 4) Anxiety Scale to measure the level of anxiety. Results: there was a highly statistically significant relation between patients' age and vital signs reading at the fourth hour after ambulation p value is<0.001, and there was a statistically significant relation between patients' age and pain intensity in the first and the second hour p value is <0.05, also there was a highly statistically significant relation between them in the fourth hour after ambulation p value is <0.001. Where pain intensity decreased among the patients at the fourth hour'. And there was no statistically significant relation between patients' gender and pain after cardiac catheterization p value is >0.05. Conclusion: Patients on supine position with restricted on bed rest increased the intensity of back pain level at a time (1h) and then decreased at the time third and fourth hour after cardiac catheterization. Recommendation: early ambulation after cardiac catheterization is safe and its' suggested to improve patients' outcomes.