Abstract: Recently multimedia,multimodal interaction and virtual reality technology are increasing quickly to improve the efficency and nature of human computer interaction,in which 3D space interaction technology plays an important role and has being applied in some fields such as CAD/CAM and scientific visualization.In the paper the authors point out the essense of direct manipulation in 3D space interaction technology,and discuss the principle and application of 3D space controller with six degrees of freedom which is the necessity for manipulating 3D objects.