miR-26, a functional miRNA, has received much attention from researchers in recent years. miRNAs may play crucial roles in numerous biological processes such as cell proliferation, apoptosis, tumorigenesis at different stages of non-tumor diseases, growth and development of normal tissues, and other biological processes. The expression of miR-26 has been found to be specific to different biological processes. Furthermore, its expression is frequently abnormal in tumors, indicating that miR-26 may play significant roles in tumor formation. Various reports exist regarding miR-26 involvement in non-tumor diseases, as well as the process of growth and development of normal tissues. In this review, we report findings of recent studies on the expression of miR-26 in different types of diseases and the process of growth and development and its predicted target genes in different tissue types. In conclusion, it is useful for researchers to understand the role of miR-26 in different biological processes.