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Objective: To analyze the clinical and genetic characteristics of pheochromocytoma and paraganglioma (PPGL), as well as genotype-phenotype correlations in children and adolescents. Methods: A retrospective analysis was performed on clinical data and germline genetic testing results of 93 pediatric and adolescent patients (age≤18 years) diagnosed with PPGL at Peking Union Medical College Hospital between January 2010 and February 2025. According to germline variant results, enrolled patients were divided into four subgroups(6 cases with variants of uncertain pathogenic significance or benign variants and 3 cases with incomplete genetic testing were excluded. A total of 84 cases were included for analysis): SDHB-mutant group(carring pathogenic or likely pathogenic SDHB variants,n=41), VHL group (carring pathogenic or likely pathogenic VHL variants, n=9), other-gene variant group (carrying pathogenic or likely pathogenic variants in alternative genes,n=8), and wild-type group (no definite pathogenic variants detected, n=26). Clinical manifestations, germline mutation spectrum, long-term prognosis, and genotype-related phenotypic discrepancies were statistically compared across groups. Results: Among the 93 patients, 54 were male and 39 were female; the mean onset age was (13.7±3.7) years, with the follow-up duration of 2.5 (1.0, 7.0) years. Follow-up was terminated in February 2026. Tumor classification included 56 paragangliomas, 34 pheochromocytomas, and 3 composite tumors with both lesions. Eighty-four patients received surgical resection. Ki-67 index≥5% was confirmed in 54% (27/50) of available pathological specimens. Postoperative tumor recurrence occurred in 21 cases, distant metastasis developed in 36 cases, and 12 patients presented with concurrent recurrence and metastasis. Germline pathogenic or likely pathogenic variants were identified in 64 patients (68.8%, 64/93), among which definite pathogenic/likely pathogenic mutations accounted for 58 cases (62.4%, 58/93): 41 with SDHB variants, 9 with VHL variants, and 8 with rare alternative-gene variants (2 cases each for SDHD and RET, 1 case apiece for SDHA, SDHC, MAX, and FH). In the SDHB-mutant group, paraganglioma accounted for 85.4% (35/41), all tumors were solitary (100.0%, 41/41), and metastatic rate reached 53.7% (22/41). In the VHL-mutant group, pheochromocytoma constituted 66.7% (6/9), multifocal lesions were seen in 77.8% (7/9), and metastatic rate was only 11.1% (1/9). Conclusions: PPGL in children and adolescents presents a strong hereditary predisposition; SDHB and VHL germline variants lead to distinctly divergent clinical phenotypes. SDHB mutations are characterized by solitary paragangliomas with high metastatic risk, whereas VHL mutations are associated with multiple pheochromocytomas featuring low metastatic risk.