Detailed descriptions and illustrations of the male genitalia in the Palearctic species of the subgenus Aedes and circumstantial data on the distribution ranges of these species are given for the first time. Four new species, Aedes alexandrei sp. n., Ae. dmitryi sp. n., Ae. nataliae sp. n., and Ae. valeryi sp. n. are described. Ae. geminus is recorded in Russia for the first time. Taxonomic positions of the species Ae. rossicus, Ae. esoensis, Ae. geminis, and Ae. cinereus are discussed with particular regards to their morphology and distribution in Russia.