High-throughput sequencing was used to study the transcriptomic changes of wildtype arabidopsis（Col-0）after salicylic acid treatment.12 novel genes downregulated by salicylic acid were identified. Among them,NG314 was studied and cloned from the cDNA of Col-0 seedlings. The total length of NG314cDNA sequence is 1 097 bp. The genomic DNA of NG314 contains one intron. Results of fluorescence quantitative PCR analyses showed that the expression of NG314 gradually decreased under the salicylic acid treatment.Pathogen infection repressed the expression of NG314. It is indicated that NG314 may encode a long noncoding RNA or novel miRNA,and may regulate plant disease resistance through repressing the expression of its target genes.