Over the last decade, STEAM has been treated as a model of interdisciplinary integral education that facilitates solving social, ecological and economic problems related to technological development in different countries. STEAM education is most efficient when it is organised in early childhood education, thus increasing children's motivation to study and to link STEAM disciplines with their career, as well as to develop as engaged citizens. The conducted empirical research revealed the following new data on STEAM at an early age: a) early childhood teachers apply practices of STEAM education that target the development of children's soft (problem-solving, creativity, ability to learn, communication) skills more frequently and employ practices for nurturance of their hard (mathematical, technological, engineering) skills less frequently ; this imbalance is favourable for the development of a proactive and critically thinking child, who is able to make decisions in a responsible way, but it does not ensure the sustainable development of STEAM abilities; b) the application of innovative STEAM education practices has effects on teacher professional development; c) STEAM practices have a bigger integral impact on the development of 3-6 year-old children's competences through the teacher professional development rather than directly.