Stenotrophomonas maltophilia is an important nosocomial pathogen with limited treatment options. Trimethoprim-sulfamethoxazole (TMP-SMX) is generally regarded as preferred therapy; however, treatment failures with TMP-SMX have been reported. Herein, we report a case of a 5-week old infant with 8 days of S. maltophilia bacteremia while receiving TMP-SMX, despite in vitro susceptibility. Transitioning to cefiderocol monotherapy resulted in blood culture clearance within 24 hours, in the absence of any additional interventions. This is the first published case of the use of cefiderocol for a pediatric patient with a S. maltophilia infection. We review pre-clinical and clinical data which underscore why cefiderocol may be an effective treatment option for S. maltophilia infections.