A method and apparatus for channel interleaving in a wireless communication system. In one aspect of the present invention, the data resource elements are assigned to multiple code blocks, and the numbers of data resource elements assigned to each code block are substantially equal. In another aspect of the present invention, a time-domain-multiplexing-first (TDM-first) approach and a frequency-domain-multiplexing-first (FDM-first) approach are proposed. In the TDM-first approach, at least one of a plurality of code blocks are assigned with a number of consecutive data carrying OFDM symbols. In the FDM-first approach, at least one of the plurality of code blocks are assigned with all of the data carrying OFDM symbols. Either one of the TDM first approach and the FDM-first approach may be selected in dependence upon the number of the code blocks, or the transport block size, or the data rate.