Background/Objectives: Decompressive craniectomy (DC) is commonly applied to manage refractory intracranial hypertension in severe traumatic brain injury (TBI). However, its role and benefits in pediatric populations remain uncertain. Clarifying whether DC provides measurable clinical advantages in children with severe TBI may inform treatment strategies and family counseling. Methods: We conducted a retrospective, one-to-one matched cohort study at a tertiary pediatric center (2014–2023). Fifty-three children with severe TBI who underwent DC were matched with fifty-three non-DC patients based on age, Glasgow Coma Scale score, cranial CT findings, and pupillary response at admission to ensure comparable injury severity. Demographic data, clinical features, and outcomes were collected. Primary outcomes were in-hospital mortality and Pediatric Cerebral Performance Category (PCPC) scores at discharge and 3 months. Secondary outcomes included duration of mechanical ventilation, intensive care unit (ICU) stay, and total hospital stay. Results: Mortality did not differ significantly between DC and non-DC groups (17.0% vs. 26.4%, p = 0.239). DC patients had better PCPC scores at discharge (p = 0.029). At 3 months, the between-group difference was not statistically significant but showed a near-significant trend (p = 0.057). No significant differences were observed in duration of ventilation (p = 0.100), ICU stay (p = 0.348), or hospital stay (p = 0.678). Conclusions: DC may not reduce short-term mortality in pediatric severe TBI but appears to be associated with more favorable neurological outcomes at discharge. Larger, adequately powered studies with standardized monitoring and longer follow-up are needed to clarify the durability and scope of potential benefits in this population.