A modern traffic setting poses complex and high requirements for all its participants, and among them, especially for children. At the age when they act as independent road users, they participate in traffic, mainly as pedestrians or cyclists. Without a doubt, the journey of children to and from school is a complex and sensitive issue. Children represent a vulnerable population from the standpoint of traffic safety. How do children view the world? What helps them link with their environment? How do children imagining traffic signs? To address this and other questions, this research examines how children react to different heights of traffic signs. This study highlights the importance of ergonomic principles in choosing the height of traffic signs for children. The main conclusion of this study is that children best perceive a traffic sign at the higher of 1.9 m and for him have the shortest reaction time.