A method for data management and a memory storage device and a memory control circuit unit thereof. The method includes: configuring a NVRAM and a VRAM; storing first data which includes writing data from a host system in the NVRAM; storing second data read from a rewritable non-volatile memory module in the VRAM; when the memory storage device is re-powered on after power failure, reading the first data from the NVRAM, so as to write the writing data into the rewritable non-volatile memory module.