Abstract: Objective: To investigate the prevalence of SDHD and SDHB mutations in patients with paraganglioma (PGL) and to provide the basis for further study of molecular diagnosis and molecular genetics of PGL. Methods:Eight spo-radic PGL cases and one familial PGL case with complete clinical and pathological data were collected. All of them were preliminarily diagnosed in our hospital duing April 2006and December 2007. We also collected blood samples from 18nor-mal people and 4 family members of the familial cases. Amplified fragments of SDHD and SDHB exons obtained through PCR were sequenced directly after purification. We used the software of BLAST to compare the results of sequencing with the standard sequences published in the NCBI net. Results: The familial case carried a heterozygotic missense mutation in SDHD. None of the 8 sporadic cases had mutations in SDHD. Two of the 8 sporadic cases carried samesense germline mutations in SDHB-exon1 and both of them had malignant leisions and an early onset. SDHB gene mutation was not found in the familial case. Conclusion:The mutation in SDHD gene may be a molecular mechnism of paraganglioma gene-sis. Genetic testing of familial cases is useful for identification of mutation carriers and early detection. Samesense muta-tion in SDHB-exon 1 A6A may affect the phenotype of paraganglioma.