Corneal densitometry is a biological property of corneal tissue, which is related to the transparency of cornea, and can be used to describe the degree of corneal transparency.At present, corneal densitometry has been used in the auxiliary diagnosis and severity evaluation of corneal diseases, as well as in the evaluation of the surgical outcome and the postoperative follow-up, even some systemic diseases affecting the cornea.The measurement of corneal densitometry is an objective, non-invasive and repeatable method to evaluate corneal transparency, which has important reference values for the monitoring of corneal and systemic health.In this article, the application of corneal densitometry in clinical practices was reviewed.