The invention discloses a 3D man-machine interaction desktop system and belongs to the user desktop design development field. The 3D man-machine interaction desktop system comprises a 3D interaction equipment layer, a 3D interaction semantic layer, a 3D interaction task layer, a 3D interaction technology layer and an application semantic layer in sequence from the bottom layer to the top layer, the application semantic layer comprises concrete application semantics, and the application semantic layer is the combination of different interaction tasks; the 3D interaction technology layer constructs, evaluates and achieves the interaction technology content and guides the interaction tasks; the 3D interaction task layer defines and distributes interaction tasks; the 3D interaction semantic layer is used for controlling the execution of interaction equipment; the 3D interaction equipment layer is located at the bottom layer and interacts with external equipment. The 3D man-machine interaction desktop system is capable of simulating objects in the real world so that the user is easier to understand and cognize, the representation mode is flexible, and the information capacity is large; the desktop 3D interaction grammar construction is easy to achieve, the semantic expression is clear, and the interaction system is convenient to define.