The invention provides a permutation and write-back adaptive buffer region management method. A buffer region is divided into a buffer block record table, a writing buffer region and a reading bufferregion. The buffer block record table is used for recording location information of data pages belonging to the same logical block in the buffer region, the writing buffer region is used for caching adata page that has been modified in response to a write request, and the reading buffer region is used for caching a data page that has not been modified in response to the read request. According tothe method, a page-level management mode is adopted in loading and erasing the data pages, by periodically and adaptively adjusting a reading buffer region threshold, the change of loading reading and writing characteristics can be sensed, thus the management method can obtain a higher cache hit rate under various load conditions. At the same time, dirty page adaptive clustering write back is used, the pressure of FTL layer garbage collection can be sensed, a write-back strategy can be adaptively adjusted, the number of extra block erasures caused by FTL garbage collection can be effectivelyreduced, and the overall performance and service life of a solid state disk is improved.