Abstract:With the development and innovation of noncoding RNA prediction algorithms and high-throughput sequencing technologies， the research on previously uncharacterized longer noncoding RNAs gradually becomes a frontier in the field. At present， large amounts of intermediate-sized and long noncoding RNAs have been identified in model plants including Arabidopsis， rice， maize， and Medicago etc. And those emerging genes accomplish variety of biological function during development and in response to environmental stimuli. Here， we reviewed the current and fast growing knowledge on the systematic identification and annotation of noncoding RNAs with the size of longer than 50 nt in higher plants. In addition， the recent advances on the regulatory mechanisms of plant long noncoding RNAs will be summarized and discussed.