A method is provided of decoding video data using a merge mode. A merge list is constructed using available spatial and temporal merge candidates. A merge candidate on the merge list corresponding to a merge index is determined as motion information of a current prediction unit. A predicted block of the current prediction unit is generated using the motion information. A transformed block is generated by inverse-quantizing a block of quantized coefficients using a quantization parameter. A residual block is generated by inverse-transforming the transformed block. A reconstructed block is generated using the predicted block and the residual block.