A system and method for analyzing an online game packet are disclosed. The system for analyzing the online game packet includes a capturing unit that captures a packet transmitted between a client terminal and a game server, and an analysis unit that analyzes the packet captured by the capturing unit, and defines, according to an analyzed result, a data field included in the packet as a static field having the same field structure or a dynamic field having a field structure according to a reference field defining an arrangement rule of a field or a field structure according to a user's request. According to the present invention, the data field of the captured packet may be defined for each type according to structural characteristics, thereby automatically analyzing the packet.