An apparatus for decoding a video by parsing asymmetric partition information indicating whether partition types include asymmetric partition types, from a bitstream of an encoded image, determining at least one coding unit included in a maximum coding unit by using split information parsed from the received bitstream, determining at least one prediction unit of a coding unit among the at least one coding unit, by using the asymmetric partition information and information about a partition type of the coding unit parsed from the received bitstream, and performing motion compensation using the prediction units for the coding unit.