Hypoxemia is defined as the condition of insufficient oxygen saturation of the blood. Hypoxemia considered as one of most dangerous problem encountered pulmonologists cardiologists and critical care nursing, it complicate the ICU stay of many children every year with significant associated mortality, it causes more than two million deaths worldwide in children less than five years of age. The study aimed to identify the best pulse oximetry placement among three placements (thumb, big toe, and ear-lobe). The study was conducted in the department of intensive care, and incubators, in Obstetric and Pediatric Hospital, and Al-Assad Hospital in Lattakia city, the sample consisted of 70 children. The results revealed that both the thumb and toe sites has an equal sensitivity in detection of hypoxemia.