Abstract: A method for fast resuming a computer system from a shutdown state is provided. The computer system comprises a basic input output system (BIOS), a system memory and a storage device storing a system memory data of the system memory and a used system memory block address table before the computer system enters the shutdown state. The method comprises receiving a starting signal for power supplying the computer system and starting the storage device. A fast boot built-in program of the BIOS is started and, according to the used system memory block address table, the fast boot built-in program sequentially reads the stored system memory data from the storage device and writes the read system memory data into the system memory with a use of an optimized read-and-write block size as a read-and-write unit. The computer system enters a suspended state and is resumed from the suspended state.