All morphs of two species of the genus Dysaphis, D. radicola (Mordv.) and D. rumecicola (Hori), living on plants of the family Polygonaceae, are described in detail. Morphometrical analysis has shown that D. radicola meridialis Shaposhnikov, 1964 is merely a synonym of D. radicola radicola (Mordvilko, 1897), and D. albocinerea (Hille Ris Lambers, 1956) and D. rheicola Daniyarova ex Narzikulov et Daniyarova, 1971, synonyms of D. rumecicola (Hori, 1935). D. emicis (Mimeur, 1935) is downgraded to a subspecies of D. rumecicola. Keys to species of the genus Dysaphis living on plants of the family Polygonaceae are provided.