The spatial pattern formed by the connection of streets and alleys with courtyards is a common spatial phenomenon in China's historical districts, which is closely related to the daily activities of residents and the development history of districts. In recent years, the research and design of the urban old city block morphology mostly focus on the relationship between the space and the form of the block, but the research on the relationship between the residents' daily behavior and the courtyard space is insufficient. Based on the theory of typology, this paper discusses the development and evolution of the common courtyard, a living place spontaneously formed by residents in a high-density historic block, from two dimensions of morphology and behavior.