Abstract:To study the specific law and the scale range of long-range correlation , series of average monthly anomaly over China from Jan. 1873 to Nov.1990 is ana lyzed with the detrended fluctuation analysis. The preliminary results show as f ollows. Firstly, there exists the long-range correlation in the average monthly temperature fluctuations. Secondly, the temperature fluctuations can be characte rized by a long-range power-law correlation with an exponent =0.66.Thirdly,the scale of 18 years can not be regarded as a crossover for the limit of the length of the series, though the exponent at large scale of more than 18 years is diffe rent from that of less than 18 years.