In order to identify novel cold-tolerance genes in rice, genome-wide gene expression profiling of Chaling common wild rice (CWR) and the cultivar indica rice Peiai 64S subjected to cold stress was perfor-med at the seedling stage using the GeneChip Rice Genome Array. A gene, designated OrCrGHl (Oryza rufi-pogon cold responsive glucan hydrolase-like), was screened from Chaling CWR as a cold-tolerance candi-date, which was highly responsive to cold stress in Chaling CWR but not in Peiai 64S. The expression pro-file of OrCrGHl obtained by the microarray analysis was confirmed by real-time quantitative PCR, suggesting that OrCrGHl is a cold-responsive gene in Chaling CWR. Its full open reading frame (ORF)-containing cD-NA clone was obtained by reverse transcription PCR (RT-PCR). Its sequence analysis showed that it encodes a glucan hydrolase-like protein of 558 amino acid residues, with a molecular weight of 59.252 kD and pI value of 5.81. The deduced amino acid sequence was completely identical with that of the glucan endo-1,3-beta-glucosidase GII isoform X2 of japonica rice Nipponbare, and was 99.28% identical with that of hypo-thetical protein OsI_26347 of indica rice 93-11. Analysis of the putative promoter region revealed several cis-acing regulatory elements that may be related to stress or stress hormone responses. The results indicated that OrCrGHl is a novel candidate gene associated with cold tolerance in wild rice. Further study is in progress to understand more about the gene.