A buffering device buffers data to be subjected to any one of a first process that necessitates a sequential guarantee and a second process that does not necessitate the sequential guarantee, and includes a storage unit that stores therein plurality of target data to be processed; a reading unit that reads the target data from the storage unit one-by-one based on a waiting flag set corresponding to the target data; and a control unit that sets a waiting flag for each of the target data, the waiting flag of a specific target data indicating preceding target data that must be processed before the reading unit reads the specific target data.