microRNA is specifically expressed in ocular tissues and plays a unique role in ocular tissues. microRNA-155 regulates a variety of signaling pathways, affects the expression of the corresponding protein, then leads to the morphology and function abnormality of cells and tissue. The mechanism of primary open angle glaucoma is not yet clear. It is considered that the morphology and function abnormality of trabecular meshwork is the main cause of the increasing intraocular pressure. The effect of microRNA-155 on primary open angle glaucoma can provide a new direction for the pathogenesis, diagnosis and treatment of primary open angle glaucoma.