Abstract: Actin, the major component of the dynamic microfilament cytoskeleton system, exists in nearly all eukaryotic cells and plays essential roles in cellular activities. In plant cells, actins are encoded by multi-gene families, and many kinds of actin isoforms have been found. This paper summarizes the research in elucidating the classes, distribution and function in vivo of actin isoforms in Arabidopsis, introduces new research into actin isoforms of pea tendril and discusses the possible future research direction in this field.