No systematic work on the study of mineral waters of Transcarpathian Ukraine was carried out before its reunification with the Ukrainian SSR. Individual sources from the point of view of their therapeutic use are briefly characterized in the Bulletin of the Czechoslovak Balneological Society. An attempt to summarize the knowledge of mineral waters of the Transcarpathian region is the work of F. Wiesner, which, however, mainly provides information of a geographical nature on more than 200 mineral springs and completely lacks data on the chemical composition of these waters. The information at our disposal at present on the chemical composition of mineral springs of Transcarpathian Ukraine allows us to outline some preliminary patterns in the distribution of various types of mineral waters by area. The Transcarpathian region, which is a young mountainous country, is characterized by the wide development of mineral waters. The number of mineral springs, according to preliminary data, reaches three hundred.