Four indexes are defined to describe the position and intensity characteristics of Siberian High (SH) based on the NCEP/NCAR monthly mean data from 1948 to 2005. By analyzing the indexes, the features of the SH's normal and anomaly variations are examined. The findings conclude that SH indexes have obvious interannual and interdecadal variations; at the interdecadal scale, SH has the trend of decreasing/diminishing with time at first, then increasing/expading; as for position variation, SH moved at first toward west, then east, and west again after 1999; the area, intensity, and central latitudes anomalies of SH are closely related to winter temperature; and the SH longitude anomaly has little effect on winter temperature anomalies. The SH abnormal area is correlated with major winter temperature anomalies at the decadal time scale. When the SH area and intensity increase abnormally, there occurs abnormal winter temperature in China, increasing in Southweast China and decreasing in the other parts of China, especially in the southern Northeast, nothern Xingjiang, and a part of Sounth China.