MicroRNA (miRNA) are small non-coding molecules consisting of 18-22 nucleotides. The studies have shown that they act as gene expression regulators at the post-transcriptional level. Their mechanism of action is based on a complementary binding to mRNA which leads to its degradation and/or blocking protein translation. The mechanism for regulating the gene expression affects a variety of cellular functions such as proliferation, differentiation and apoptosis. Fibrosis is a very complex disease whose main characteristic is the excessive accumulation of extracellular matrix proteins leading to the abnormal organ function. The disease can develop as a result of frequent injuries, or as an aftereffect of a single tissue injury. Fibrosis can affect various organs, most often the heart, liver, lung, and kidney. It is believed that the miRNA molecules are involved in the processes of fibrous development and because of that, this work aimes at clarifying the role of miRNA and provides an overview of the identified miRNA molecules and their molecular targets that regulate different signal pathways thus participating in the development of the disease. We can state with certainty that miRNA molecules play a significant role in the emergence and the development of the fibrosis. Scientists believe that by manipulation of the expression of miRNA it is possible to slow down and/or stop further progression of the disease. The miRNA molecules provide great hope and potential for the development of innovative therapies and new ways of treating fibrosis, and many other related diseases.