Background:Stenotrophomonas maltophilia (S. maltophilia) is an opportunistic and nosocomial pathogen that can cause an invasive and fatal infection, particularly in hospitalized and immunocompromised patients. However, little is known about the impact of S. maltophilia bacteremia in pediatric patients. Therefore, we aimed to identify risk factors for mortality, antibiotic susceptibility of S. maltophilia, and mortality rates in pediatric patients with S. maltophilia bacteremia. Methods: We conducted a retrospective cohort study by identifying all S. maltophilia–positive blood cultures in the microbiology laboratory database between January 2007 and December 2018 from hospitalized pediatric patients (age, 1–14 years) at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. After identifying patients with S. maltophilia bacteremia, medical charts were reviewed for demographics, clinical data, and outcome within 7 days of bacteremia diagnosis. Risk factors associated with mortality in S. maltophilia bacteremia patients were determined using univariate and multivariate analyses. Results: Overall, 68% of pediatric patients with S. maltophilia bacteremia were identified. The most common underlying primary diagnoses were malignancy (29.4%), congenital heart diseases (16.2%), anemia (14.7%), and primary immunodeficiency (11.8%). All infections were nosocomial infections, and (88.2%) bacteremia cases were central-line–associated bloodstream infections. The risk factors associated with mortality as determined by univariate analysis were ICU admission (P < .001), intubation (P = .001), neutropenia (P = .008), prior use of carbapenem (P = .002), thrombocytopenia (P = .006), and respiratory colonization (P < .001). On multivariate analysis, ICU admission (P = .007; 95% CI, 0.003–0.406) and neutropenia (P = .009; 95% CI, 0.013–0.537) were the major risk factors associated with mortality. S. maltophilia was the most susceptible to trimethoprim and sulfamethoxazole (TMP/SMX, 94.1%), followed by levofloxacin (85.7%). In addition, 36 patients received TMP/SMX as monotherapy, and 11 patients received it in combination with other antibiotics (fluoroquinolone, ceftazidime, or aminoglycoside). Hence, no statistically significant difference was observed in patient mortality. The overall mortality rate within 7 days of S. maltophilia bacteremia diagnosis was 33.8%. Conclusions:S. maltophilia bacteremia is a devastating emerging infection associated with high mortality among hospitalized children. Therefore, early diagnosis and prompt management based on local susceptibility data are crucial. Various risk factors, especially ICU admission and neutropenia, are associated with S. maltophilia bacteremia mortality.