The article presents an analysis of chromosome numbers in Siberian species of the genus Viola (40 speciesfrom 12 sections) based on numerous literary sources and original data. In addition, hybrid forms from the collection site“Rare and endangered Plant Species” of the Central Siberian Botanical Garden (Novosibirsk) were analyzed. Just as theroots of germinated seeds, so the roots of adult plants from an open ground area were studied. Samples of different originswere investigated: Siberia, the Far East, Mongolia, Belarus, Korea, Japan, the Caucasus, in some taxa from remote points ofthe area (for example, V. selkirkii). This allowed us to reveal the variability of the chromosome numbers for some species.Chromosomes in species of this genus are small, 0.8–1.2 mkm long. This involves difficulties to count them. The presenceof mixoploids in some sections and the polybasic state of chromosome numbers for a number of species were established.Polymorphic species in the Violidum section are characterized by polyploid races. The variability of chromosome numbersin taxa reflects their ability to hybridize, as well as the processes of speciation. However, the predominance of autogamy formost species of the genus prevents intensive hybridization. Endemic and tertiary relicts are characterized by a stable number of chromosomes and they are tetraploids.