Abstract: WRKY transcription factors act as important regulatory molecules， and exist in the form of gene family in higher plants. In this study， genome-wide identification and analysis of WRKY transcription factors in Brassica rapa ssp. pekinensis were performed with bioinformatic methods using genomic data. We identified 134 WRKY transcription factors with protein sequence length varying from 143 to 1 082. Their full length genomic DNA were 880 to 9 099 bp in size with 1-15 introns. Location analysis of WRKY genes indicated that they distributed on all 10 chromosomes. Most of the WRKYs were present on chromosome A3 （26）， while the fewest on A10 （4）. WRKY transcription factors can be divided into three major groups located at different branches of the phylogenetic tree. The gene numbers of Ⅰ， Ⅱ and Ⅲ groups were 27， 83 and 24， respectively. Three new types of WRKY domains， WRKDGQK, WRKNGQK and WMKYGQK， were indentified in addition to conserved WRKYGQK and its common variant WRKYGKK sequences.

Key words: Chinese cabbage, WRKY transcription factor, genome-wide, sequence analysis