The inventive embodiment discloses a method for identifying data stream of massive multiplayer online role playing game (MMORPG), which includes counting the quantity of data packs in available loadsof data stream in each period; dividing the quantity of the counted data packs into at least two clusters; determining the reliability of each cluster according to the ratio of number of sub-sequenceof each cluster in a set time to the number of stream gathering periods of MMORPG in the set time, which is integer times of the stream gathering period of MMORPG; and determining the data stream is MMORPG data stream if the reliability of one of the clusters is larger than a set threshold. With the inventive embodiment, the problem existing in prior art that the MMORPG data stream can not be accurately identified can be solved. The inventive embodiment simultaneously discloses a device for identifying data stream of massive multiplayer online role playing game.