The paper presents data on psychological states (PS) of pre-schoolers aged from 3 to 7, discussing common characteristics as well as specificity of PS in different age periods, types of PS and their dynamics (main tendencies, peculiarities in the realization of these states by children of different age groups). The authors discuss interrelations between PS on the one hand and psychological traits and cognitive processes on the other, identifying stages in the development of self-regulation of PS in pre-school children of different ages.