As a novel class of endogenous non-coding RNAs, circular RNAs (circRNAs) have become a new research hotspot in recent years. The wide distribution of circRNAs in different plant species has been proven. Furthermore, circRNAs show significant tissue-specific expression patterns in plant development and are responsive to a variety of biotic and abiotic stresses, indicating that circRNAs might have important biological functions in plant development. Here, we summarize the current knowledge of plant circRNAs in recent years and discuss views and perspectives on the possible regulatory roles of plant circRNAs, including the function of miRNA sponges, regulating the expression of their parental genes or linear mRNAs, translating into peptides or proteins and responses to different stresses. These advances have sculpted a framework of plant circRNAs and provide new insights for functional RNA regulation research in the future. (C) 2017 Elsevier Inc. All rights reserved.