Obstacle scene is one of the common methods of its expression. It organizes, extends and creates a rhythmic space together with borrowing scenes, contrasting scenes and framing scenes. The main performance is to use some material to separate a space into two interconnected "pseudo" composite spaces. It makes the landscape of the garden to be hidden before being exposed and gradually displayed in front of the tourists layer by layer, making people unable to see at a glance or wear it, and making it more attractive and exciting. Private gardens in the south of the Yangtze River often use rocks, hedges, plants, buildings and so on as barrier materials. The texture, volume and form of different materials all affect the impression of garden space to visitors. The following is a breakdown of different materials, one by one analysis.