Complex-cultural facilities in the contemporary era are significantly influenced by the anti-modernism and space relativism movement of the 20th century. Complex-cultural facilities have the complex-layered space. In many contemporary buildings, this complex-layered space has void center space within it which primarily functions as indoor plaza. This study pays attention to the fact that the design of indoor plaza has developed differently in Europe and the US, which vividly demonstrates spatial relativism in contemporary buildings. With this backdrop, I analyze the architectural and cultural backgrounds of indoor plaza in Europe and the US. In addition, I examine the cultural functions and visual interpretation of indoor plaza in the regions to compare the design features and functionality.