Nevoid basal cell carcinoma syndrome (NBCCS) is a rare pleiotropic autosomal dominant disease predominantly characterized by the occurrence of multiple basal cell carcinomas, odontogenic keratocysts (OKCs) of the jaw, and other developmental defects. Mutations in the human patched gene (PTCH) have recently been detected in patients with NBCCS. We report the clinical manifestations of a Taiwanese family with NBCCS and mutation analysis of the PTCH gene from peripheral blood, OKC tissues, and cyst content. A heterozygous A-to-G transition at nucleotide 3169-2 within the intron 18 (3169-2 A>G) was found. The cystic membrane and the cystic content showed the same results. Mutation analysis can provide a reliable prenatal diagnosis of this syndrome in subsequent pregnancies.