According to the results from the 2011 Census, in Autonomous Province of Vojvodina (hereinafter referred to as ’Vojvodina’) there were 1,815 Slovenians, or 45% of the total number of Slovenians in the Republic of Serbia. Slovenians make up only 0.09% of the total population in Vojvodina. All demographic indicators show a profound demographic decline in the population based on biological depopulation that began in the late 1960s. Furthermore, a negative trend in natural increase was further strengthened by inverse migrations that started several years after they had colonized Vojvodina, especially south Banat. Slovenians in Vojvodina, at an average age of 52.1 years, were ranked second place in the rank of ethnicity by age, which clearly indicates to intense process of population ageing and inability to achieve positive effects of natural movement. Although this population is statistically small in number, this paper clarifies the underlying causes of extremely unfavorable demographic trends that characterized Slovenian population in Vojvodina over the last several decades.