Background: To evaluate the role of the trans-abdominal ultrasound (TAUS) in the assessment of hemidiaphragmatic dysfunction-due to non-pulmonic causes-as compared to the conventional CT; 36 patients (22 males and 14 females; age range 5 to 84 years) were included in this study. Results: In CT examination, the dysfunctional hemidiaphragm was considered when either a hernia/post-traumatic defects (present in 19.4% of patients, of which 5.5% were depicted on the right side and 13.8% were existing on the left side), or elevated copulae (present in 80.6% of patients, of which 58.8% were found on the right side (21 patients) and 22.2% were seen on the left side (8 patients). The TAUS showed a high sensitivity, specificity, PPV, NPV, and over all accuracy {100% (95% CI = 59.04 to 100.00%), 100% (95% CI = 88.06 to 100.00%), 100%, 100%, 100% (95% CI = 90.26 to 100.00%), respectively} in detection of defects and hernias as compared to CT. A high sensitivity, specificity, PPV, NPV, and over all accuracy {96.55% (95% CI = 82.24 to 99.9%), 100% (95% CI=59.04 to 100.00%), 100%, 87.5% (95% CI = 50.50 to 97.96%), 97.22% (95% CI = 85.47 to 99.93%), respectively} were found in detection of thickness and motion abnormalities, and in the detection of subphrenic collections in cases with relevant elevated copula in CT. Conclusion: Trans-abdominal ultrasound (TAUS) could accurately assess the diaphragmatic thickness and provides a real-time image of a dysfunctional hemidiaphragm due to a diaphragmatic and infradiaphragmatic causes as well as the diaphragmatic defects with high sensitivity and specificity in comparison to CT.