Early Childhood Education is the first foundation that is essential in intervening the child cognitive development. Many methods can increase cognitive development which of them is method based on Science, Technology, Engineering, Art, and Mathematics (STEAM) with Loose Part media. This study aims to examine the effectiveness of learning using the STEAM Loose Part method on cognitive development in early childhood. The researcher used descriptive qualitative analysis, content analysis, and library research in written texts to relevant documents. This research exhibits the learning effectiveness and cognitive development in early childhood such as the enhancement of creativity, problem-solving, and others after employing the STEAM Loose Part method. Here, STEAM loose Part learning stress out in freedom to explore, solve, and think so that the children can have space to think, evaluate, and determine the best way to achieve their goals and complete the project.