Bacteria of the genus Wolbachia constitute a group of intracellular and maternally inherited micro-organisms that are widespread in arthropods, inducing several reproductive disorders such as cytoplasmic incompatibility in their hosts. Considering relevant biological implications related to the presence of Wolbachia in several insect orders, for example its potential role as mechanism for rapid speciation and as vehicle to drive genetic markers in wild populations of vectors of medical and veterinary interest, we carried out an extensive polymerase chain reaction survey to detect Wolbachia in several species of mosquito belonging to genera involved in the transmission of pathogens. Five species out of 26 tested have shown to be infected; for four of them this is the first evidence of the Wolbachia infection. A phylogenetic analysis was also performed, positioning the five Wolbachia strains in the phyletic subdivision B.