Exosome is a nanoscale membranous vesicle formed by fusion of multivesicular body with cell membrane and secreted into the extracellular matrix, playing important roles in the intercellular communication of cells. Mesenchymal stem cell (MSC)-derived exosome (MSC-exo) is an important paracrine pathway of MSC to promote tissue injury repair and immune regulation. Compared with the MSC, MSC-exo has specific advantages. Recent research reveals that MSC-exo targets the damaged tissues to ameliorate kidney injury by delivery of protein, mRNA and microRNA. In this review, we summarized the research progress of MSC-exo in kidney diseases.