Background: respiratory distress is the primary diagnosis in nearly 50% of children admitted to the pediatric emergency room and is a common cause of cardiopulmonary arrest in children. There is substantial variability in the etiology and severity of illness. The presenting clinical findings usually help to determine the type of problem. The causes include pneumonia, bronchial asthma, pneumothorax, acute bronchiolitis and pleural effusion. Objective: the present study was designed to compare chest ultrasound, as a diagnostic tool in the diagnosis of children with acute conditions of RD with the diagnosis of other radiological tools (Chest X-ray and CT chest. Methodology: this study included 200 infants and children, attending the Paediatric Department in Sayed Galal and Al- Hussein, AL-Azhar University Hospitals and they were suffering from respiratory distress. Their ages ranged from 12 month to 60months with mean age 32.52 months ± 13.91 months. Males were 134/200 (67%) while, females were 66/200 (33%) with male to female ratio 2.03:1. Results: as regard distribution of patients according to clinical or radiological diagnosis, the study showed that uncomplicated pneumonia n84 (42.0%), pneumonia with effusion n32 (16.0%), non pneumonic effusion n8 (4.0%), lung abscess n4 (2.0%), pneumothorax n14 (7.0%), lung collapse n16 (8.0%), mediastinal mass n4 (2.0%) and acute bronchiolitis n38 (19.0%). Conclusion: from our study, we can conclude the following:in view of our study it can be concluded that, chest US offers an important contribution to the diagnostic procedures of pleuro-pulmonary disorders in children, as pneumonia, pneumothorax, pleural effusion, lung abscess, lung collapse, mediastinal mass and acute bronchiolitis.