Abstract: As a new carrier of human survival and consciousness activities， 3D virtual space takes the terminal of electronic equipment as the interface and is supported by network communication technology， virtual reality technology and 3D modeling technology， breaking through the shackles of gravity and structural mechanics in physical space. It presents spatial characteristics such as virtuality， fluidity， cross-media and hyperlinked， releasing new aesthetic opportunities for spatial aesthetics. The aesthetics of 3D virtual space is constructed around the aesthetic subject “human”，and the physical experience， sensory intake and emotional projection of the aesthetic subject are transformed into spatial practice through the“virtual body”.Deeply influenced by science fiction culture and internet culture， the 3D virtual space integrates technological worship and spatial metaphor， pointing to the spatial representation of knowledge and power. Internet “decentralization”as a social representation of 3D virtual space has realized its transformation and transcendence of real space in terms of material relations，production relations and social relations.“Decentralization”extends the discussion of spatial autonomy such as spatial discourse， spatial power， and spatial justice， so that virtual space extends spatial aesthetic reflection and postmodern aesthetic criticism.