The invention provides a file segmentation method based on file time-domain access features and a calculation method of fragment popularity. The method comprises the steps of analyzing access featuresof a file on time domain, estimating the probability of being broadcasted in different time periods of the file, segmenting the media file into data fragments with different lengths according to userbroadcasting tendency, then calculating the popularity of each segmented fragment and further obtaining more accurate popularity information of the file in the different time periods. The file segmentation method based on the file time-domain access features and the calculation method of the fragment popularity carry out reasonable division on the big file aiming at the differences of the file time-domain access features, carry out duplicate placement by taking fragment as unit, segment the big file into the lengthened fragments, lead a network to provide more service for the important fragments with pertinence, and improve the utilization rate of space and simultaneously increase the hit rate of user access content.