In the current boom of Virtual Reality, or VR, the related philosophical research has not attracted enough attention yet, leading to the wide controversy and divergence about the concept of VR. In this article, in order to find out the basic essence of the VR, its four important philosophical dimensions are discussed. As concluded by the author, born with the help of modern computer technology, VR is a digital virtual space, whose essence is pure information.Far more than just simple formal simulation, the nature of virtualization is using electronic media technology to give the users an equal sensory experience as what they can get in the outside physical space or idealized illusion space, and this kind of virtualization, which has functional equivalence, is common in human media technology. Users’ immersive experience in VR space comes from their own fusions on the media interface with the digital information space. As a result of the fusion of human, information and machine, human beings will transform to the cybernetic organism cyborg, which has the character of hybrid subject as well as the posthuman.