Abstract: Based on the daily precipitation data of 70 stations selected evenly over China from 1961 to 1991, three estimating methods on climate noise of monthly precipitation are discussed. The climate noises of monthly precipitation in January, April, July and October are estimated by using the improved methods. The results show that with the precipitation increasing, the climate noise of monthly precipitation would increase and has obvious seasonal change. Generally, the value of climate noise is greater in summer than in winter. In spatial distribution, the climate noise in the most areas of China decreases prominently from south to north, and from coastal areas to inland all the year round.