A method of constructing a merge candidate list for video coding, comprising: constructing merge list; obtaining motion information using a merge index and the merge list; generating a prediction block using the motion information; and generating a quantization block by inverse-scanning quantized coefficient components according to diagonal scanning, inverse-quantizing the quantization block by using quantization parameter, and generating a residual block by inverse-transforming the inverse-quantized block, wherein the merge list is constructed by performing sub-steps of: checking availability of spatial merge candidates; checking availability of a temporal merge candidate; constructing the merge list using available spatial and temporal merge candidates; and adding one or more candidates if the number of available spatial and temporal merge candidates is smaller than a predetermined number, wherein the spatial merge candidates are motion information of spatial merge candidate blocks, and the spatial merge candidate blocks are a left block, an above block, an above-right block, a left-below block or an above-left block of the current block, wherein if the current block is a second prediction unit partitioned by asymmetric partitioning, the spatial merge candidate corresponding to a first prediction unit partitioned by the asymmetric partitioning is set as unavailable, wherein the quantization parameter is generated using a differential quantization parameter and a quantization parameter predictor, and the quantization parameter predictor is generated by averaging the first two available quantization parameters in an order of a left quantization parameter, an above quantization parameter and a previous quantization parameter if two or more quantization parameters are available, and wherein, when only one of the left quantization parameter and the above quantization parameter is available, the quantization parameter is generated using an average of the available quantization parameter and a previous quantization parameter. constructing merge list; obtaining motion information using a merge index and the merge list; generating a prediction block using the motion information; and generating a quantization block by inverse-scanning quantized coefficient components according to diagonal scanning, inverse-quantizing the quantization block by using quantization parameter, and generating a residual block by inverse-transforming the inverse-quantized block, wherein the merge list is constructed by performing sub-steps of: checking availability of spatial merge candidates; checking availability of a temporal merge candidate; constructing the merge list using available spatial and temporal merge candidates; and adding one or more candidates if the number of available spatial and temporal merge candidates is smaller than a predetermined number, checking availability of spatial merge candidates; checking availability of a temporal merge candidate; constructing the merge list using available spatial and temporal merge candidates; and adding one or more candidates if the number of available spatial and temporal merge candidates is smaller than a predetermined number, wherein the spatial merge candidates are motion information of spatial merge candidate blocks, and the spatial merge candidate blocks are a left block, an above block, an above-right block, a left-below block or an above-left block of the current block, wherein if the current block is a second prediction unit partitioned by asymmetric partitioning, the spatial merge candidate corresponding to a first prediction unit partitioned by the asymmetric partitioning is set as unavailable, wherein the quantization parameter is generated using a differential quantization parameter and a quantization parameter predictor, and the quantization parameter predictor is generated by averaging the first two available quantization parameters in an order of a left quantization parameter, an above quantization parameter and a previous quantization parameter if two or more quantization parameters are available, and wherein, when only one of the left quantization parameter and the above quantization parameter is available, the quantization parameter is generated using an average of the available quantization parameter and a previous quantization parameter.