Age-sex structure of Slovenians in Vojvodina is elaborated in this paper. Particular attention was given to the period after the World War Second. Identification of tendencies in age structure of Slovenians was the main task of the paper. Statistic methods and mathematics proceedings are used to compare different parameters of age structure (e.g. middle age, index of ageing etc). The paper confirms that Slovenians are one of the oldest ethnic groups in Vojvodina population. Results will enrich knowledge about Slovenians in Vojvodina. They might be used in function of demography.