Introduction: Hypoxemia is defined as a low amount of oxygen in our blood. Earlyrnpostoperative hypoxemia leads to cellular ischemia which may delay recovery and complications rnare associated with significant cost and mortality implications for patients. rnObjectives: The objectives of the study was to determine the magnitude and associated factorsrnof hypoxemia in pediatric patients aged 1-14 years who undergone surgery under general rnanesthesia in Tikur Anbessa specialized hospital from October 26, 2019 to February 26, 2020rnG.C. rnMethod: Institutional based cross sectional study was conducted at Tikur Anbessa specializedrnHospital, Addis Ababa, Ethiopia data was collected from October 26/2019 to February 26, 2020rnusing a pre-tested questionnaire starting from preoperative period to postoperative period inrnPACU. After sample size was calculated and systematic random sampling technique applied, 229rnpatients included in the study. The data was entered to Epi Info version 7.2.1 and analyzed byrnSPSS version 22 software performing descriptive statistics, bivariate and multivariate logisticrnregression. rnResult: The incidence of early postoperative hypoxemia is found to be 44.5%. Muscle relaxantrnuse has a 3.13 times [AOR=3.13; 95% CI: (1.13-8.64)] and not using premedication has 10 timesrn[AOR=10.93; 95% CI: (4.74-25.21) more risk for developing early post-operative hypoxemia.rnDuration of surgery greater than an hour has 4.6 times [AOR=4.68; 95 % CI: (2.01-10.89)] andrnduration of anesthesia greater than an hour has 11 times [AOR=11.29; 95% CI: (3.96-32.19)]rnrisk for early post-operative hypoxemia. rnConclusion and recommendation: The magnitude of early postoperative hypoxemia is high.rnSome of the identified factors were muscle relaxant use, duration of surgery and anesthesiarngreater than an hour therefore itâ€™s important to give attention for patients undergoing longrnsurgical procedures and for patients who took muscle relaxants.