Abstract: The virtual nuclear reactor is a sophisticated software system deployed on supercomputers to simulate physics processes or predict component behaviors inside real reactors. It heavily relies on advanced modeling and coupling methods, high performance computing and advanced verification and validation (V&V) techniques. It is supposed to provide an experimental verification platform for the design optimization of advanced nuclear reactors, efficient operation, accident prediction, emergency planning, and the development of new materials. In a word, the system is an “external” and “internal” mirror image of real reactors. Based on a brief overview of the research results of typical virtual nuclear reactors at home and abroad, the core software component of virtual nuclear reactor was explained, the high requirements for computing speed and storage were analyzed, and the recent achievements of the prototype of China Virtual Reactor (CVR1.0) were presented in this paper. The recent achievements of CVR1.0 contain some of its simulation tools including the two-phase sub-channel thermal hydraulic simulation software, the single-phase CFD thermalhyd-raulic simulation software, the multi-scale materials irradiation damage simulation software, and the method of characteristics software for direct 3D neutron transport simulation. Comparisons among these tools and their counterparts from CASL, NEAMS, and RPV in the U.S.A or Europe are made and listed concisely, as well as the results of performance analyses on supercomputers such as Sunway and Sugon series.