This paper is to clarify a cognitive structure and behaviors of the green environment creation in the Western-Style residential areas. The followings are the results of analysis; 1) Regarding the outside space of houses, yard and garden are differently recognized. While various behaviors are carried out in the yard, the garden is recognized as a space to construct green environment. 2) Most residents of Western-Style houses construct the outside space as a green space, and grow plants and flowers to enjoy their beauties. However they have introvert view of green environment. 3) The roles of outside space use are classified into four groups, the cognitive structures on the green environment creation are different from group to group.