The issue of attracting investments is one of the key issues in modern society. The global experience shows that sustainable economic development and growth are determined by the volume and structure of investments. Therefore, the study into the investment environment where the investment activity happens – the investment climate, is becoming increasingly relevant. The prerequisites for the study into the investment climate have been formed since the Keynesian economic theory; studies into the investment climate have become widely spread in modern economic theories. Starting with the Keynesian economic theory and until modern theories of investments, the factors that influence the investment climate can be divided into two groups: investment potential and investment security of the region. According to the outcomes of the factor analysis of Latvia’s regions (Riga, Pieriga, Vidzeme, Kurzeme, Zemgale, and Latgale regions), Lithuania’s regions (Vilnius, Alytus, Utena, Panevezys, Kaunas, Klaipeda, Marijampole, Taurage, Telsiai, Sauliai counties), and Belarus’ regions (Vitebsk, Grodno, Mogilev, Minsk, Gomel, and Brest oblasts, and Minsk city), the factor of socioeconomic security is adeterminant of regional differences in the investment climate.