Disclosed are a method for predicting a current block using a current picture referencing mode (also called intra block copy (ibc) mode), and a video encoding or decoding device therefor. The method comprises: decoding, from a bitstream, an enable flag indicating whether the application of the ibc mode is allowed, and type information indicating whether the type of slices is an inter type; depending on the enable flag and the type information, decoding from the bitstream an ibc flag indicating whether a prediction mode for the current block is the ibc mode; when the ibc flag indicates the ibc mode, decoding motion information from the bitstream; and predicting the current block by using a block indicated by the motion information within a current picture in which the current block is located.