It is shown by the principal component analysis of the annual andseasonal mean temperature series of 42 stations in China during theperiod of 1881-1981 that the whole country can be divided into fiveareas according to the spatial distribution of the variance contribu-tion of the principal components to the temperature series in eachstation. During the past hundred years the trend of the annual andseasonal mean temperature in the most part of China was very simi-lar to that of the mean temperature in the northern hemisphere. It isalso shown by the analysis of variance spectrum of the first threeprincipal components that the significant statistical period was variedfor different components, but most of them were concentrated in thethree wave bounds, i.e.. wave bounds of 18.4-28.9, 2.9-3.0 and 2.2-2.3 years and the periodic component of 18.4-28.9 years coincidedwith the phase of the double 11-year sunspot cycle.