An event processing method and apparatus which relate to the field of data processing technologies and applicable to a device on which a system having a pattern matching function runs, and reduce memory overheads when a complex event processing (CEP) system performs pattern matching in a complex scenario. The method includes performing, by a state machine instance, matching in a current matching period after an Xth event occurs, detecting, by the state machine instance, whether a quantity of events that have currently occurred is greater than 1 when no result indicating successful matching is obtained, and setting a time when an (X+1)th event occurs as a start time of a next matching period when the quantity of events that have currently occurred is greater than 1, and performing matching again in the next matching period.