There is a significant unmet medical need for effective therapies for pediatric relapsed/refractory solid tumors. EGFR is highly and stably expressed in multiple pediatric solid tumor subtypes, and adult Phase I data of Becotatug Vedotin demonstrated a manageable safety profile and promising antitumor activity in EGFR-positive advanced solid tumors.This is a multicenter, non-randomized, single-arm, open-label Phase I clinical trial sponsored by Sun Yat-sen University Cancer Center (SYSUCC). The trial evaluates the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary efficacy of Becotatug Vedotin-an EGFR-targeted antibody-drug conjugate (ADC)-in pediatric patients with EGFR-positive relapsed/refractory or metastatic solid tumors.