Exosomes play an important role in rejection after organ transplantation. Different cells secrete exosomes to activate different cellularmolecular signaling which ultimately leads to kidney rejection or transplantation. To shed some lights on this issue, this paper aimed at reviewing the related articles published between the years of 2005 and 2020, and retrieved from Pubmed database and Google scholar search engine using the keywords “exosome”, “kidney transplantation”, “diagnosis”, and “rejection”. The findings show that exosomes secreted by immune cells express the surface markers of the origin cell and exert their influence on the target cells according to the function of the stem cell. Generally, almost all cells involved in immune responses secrete their own exosomes, which transmit their contents to cause genetic and phenotypic changes in receptor cells. Since the secretion of exosomes from immune cells increases after kidney transplant rejection and the markers on the surface of the enlarged exosomes indicate the presence of the secreted cell, it is possible to inhibit the signaling pathways caused by the exosomes through monitoring the patient’s clinical process after transplantation.