In the 1960s, when apartments were being introduced in South Korea and were not yet standardized, diverse attempts at construction were made. However, due to factors such as the preference for houses that face south, apartment planning principles were unified. The present study intended to find out characteristics that can be applied to the current demands by studying cases of experimental plans among apartments, understanding the plans of courtyard apartments and classifying the cases into different types. The types of 29 courtyard apartments constructed in 1960–1970s in Seoul were analyzed. The apartments were classified into complex types that refer to cases where many buildings form a courtyard, block types, and open types.