Coenuriasis is a parasitic disease induced by larval taeniid tapeworms that is rarely observed in humans. In December 2005, a case was diagnosed in Nancy, France, after surgical excision of a cyst on a 24-yr-old woman returning from the Côte d'Ivoire. Morphological and epidemiological criteria suggested that the infection was due to Taenia serialis. Molecular analysis of NADH dehydrogenase subunit I (NDI) and cytochrome c oxidase subunit I (COI) sequences was also in favor of T. serialis identification, but the absence of available genetic data on T. brauni and T. glomeratus and the small number of published sequences for T. serialis and T. multiceps must be considered with caution. The NDI partial sequences presented more variations within species of Taenia than the COI sequences, which make them more useful targets for species identification and analysis of intraspecific polymorphisms. The present study points to the usefulness of molecular biology tools to help make up for the shortcomings of the commonplace parasitological diagnosis for coenuriasis.