Purpose: Lesson study is one of the most adopted models of teacher professional development. However, as education has become increasingly digital, this study aims to investigate the use of digital tools to support teacher professional development in lesson studies. Design/methodology/approach: This article systematically reviews journal articles on the use of digital tools to support teacher professional development in lesson studies. Findings: While the lesson study model is typically based on the premise that teachers prepare and observe a lesson at a school, the reviewed research suggests that digital tools open new ways to conduct lesson studies. Six themes on the use of digital tools to support teacher professional development in lesson studies are identified: analyzing videos from the teachers' classrooms, analyzing external video resources, fictional animations as a complement to videos, structured digital lesson study work, hybrid teacher collaboration and digital teacher collaboration. Opportunities for further research are suggested. Practical implications: The identified themes can inspire practice on how to use digital tools to support teacher professional development in lesson studies. Originality/value: Little attention has been paid to the use of digital tools to support teacher professional development in lesson studies.