Introduction: Facing the recognized obstacles of chest computerized tomography (CT) and chest x-ray (CXR), lung ultrasound (LUS) is a promising alternative imaging tool gathering the benefits of real-time diagnosis with lower difficulties. This study aims to evaluate the effectiveness of LUS as a diagnostic modality in surgical critical care in contrast to chest x-ray. Patients and Methods: In this study, for each of the 92 included patients, when chest CT is indicated, CXR was requested and the BLUE protocol for LUS examination was initiated simultaneously. LUS data were recorded while analysis of CXR finding was performed by independent radiologist who was unaware of CT or LUS findings. Results: For each patient, 4 lung areas were examined with LUS and compared to CXR. LUS showed higher specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy (DA) of LUS in contrast to chest x-ray. A significantly lower time was required for LUS to reach the diagnosis compared to CXR (10.2± 4 minutes vs. 33±17 minutes respectively, p less than 0.01). Conclusion: LUS is a useful tool in screening and diagnosis detection of various pulmonary problems in surgical ICU; it can be used as daily bedside diagnostic tool for the critically ill patients adding the use of other chest imaging modalities.