Is there an algorithm that supports transforming from CGCS2000 coordinate to WGS84 coordinate? CGCS2000 is China Geodetic Coordinate System 2000.
Any advice would be thankful!
According to spatialreference.org, CGCS2000 should be
+proj=longlat +ellps=GRS80 +no_defs
The usual approach is to add this definition as a custom CRS if you cannot find it in the default CRS list of QGIS.
The EPSG registry lists two versions of CGCS2000:
EPSG:4479uses a 3-dimensional cartesian coordinate system based on the Earth's center
EPSG:4480uses Latitude, Longitude and ellipsoidal height.
For the first one, see Help defining custom CRS in QGIS 2.2 how to use it in QGIS and the limitations of that CRS.
For the second one, you can use the projection string that underdark suggested.