Antimicrobial resistance (AMR) is a major public health challenge, particularly in low- and middle-income countries (LMICs), where antimicrobial stewardship (AMS) is often lacking. This study assessed the knowledge, attitudes, and practices of healthcare professionals in pediatric settings regarding AMR and AMS at Maputo Central Hospital, Mozambique. Methods: A cross-sectional survey was conducted among pediatric healthcare professionals using a self-administered questionnaire. Descriptive and inferential statistical analyses were performed to assess knowledge, attitudes, and practices, and their associated factors for inappropriate prescribing. Results: Of 108 eligible participants, 82 (76%) responded to the questionnaire. Overall, 53 (66%) correctly identified that antimicrobials do not treat viral infections, and 79 (99%) recognized factors contributing to AMR. However, only 28 (34%) were familiar with the concept of AMS programs, and participant knowledge related to empiric antibiotic selection was suboptimal. Physicians had significantly higher knowledge scores than laboratory technicians (p = 0.036). Prior AMS training was strongly associated with improved knowledge (p < 0.001) and better prescribing practices (p = 0.005). Despite 71 (92%) participants acknowledging AMR as a major issue, only 30 (37%) recognized their personal role in its emergence. A majority, 77 (94%), expressed interest in further AMS training. Conclusion: Pediatric healthcare professionals at Maputo Central Hospital are generally aware of AMR and exhibit positive attitudes toward AMS. However, notable gaps exist in their knowledge and practices. Strengthening AMS education, increasing access to treatment guidelines, and integrating AMS training into routine professional development are recommended to improve appropriate antimicrobial prescribing. These findings support interventions that are aligned with Mozambique’s National Action Plan on AMR.