The author analyzes some aspects connected with the dynamics of changes in the number of Karaite population on the territory of south-eastern provinces (goubernias) of the Russian Empire at the end of the 18th - the beginning of the 20th centuries. Demographic statistics in Karaite communities and the geography of settlement of the Karaites are examined. Materials of Russian censuses of the population of the end of the 18th - the end of the 19th centuries, statistic reviews, reports and data published in various reference books, guide books, address-calendars as well as in "Memorial books" of Russian provinces, archive documents; some of them and data revealed in pre-revolutionary periodicals are introduced into scientific circulation for the first time. The author came to the conclusion that in the period since the end of the 18th - the beginning of the 19th centuries the number of the representatives of Karaite communities of Taurida province began to increase gradually. The statistics was changing in connection with the indexes of birth and death rates as well as a result of internal migration of Karaite population on the territory of the Russian Empire. During the 19th century the Karaites from traditional places of residence started to settle in southern and central provinces; Karaite communities appeared in many Russian towns. By the end of the 19th century total population of the Karaite population measured up to 12,894 people. Despite some negative moments connected with the work of departments of statistic control to get data (bureaucracy of officials, imperfection of methods of statistics record, etc), the data of censuses are the source of information on statistics of Karaite population of the Russian Empire of the end of the 18th - the beginning of the 20th centuries.