Abstract:Herpes simplex keratitis (HSK) is a corneal infection caused by herpes simplex virus type 1(HSV-1). Its incidence rate and blindness rate row the forefront of corneal diseases. Because of the nerve susceptibility of herpes simplex virus, the corneal nerves of HSK patients are reduced. HSK is prone to corneal nerve atrophy, corneal hypoesthesia and loss of epithelial integrity. The more serious situation is corneal ulcer, dissolution and even perforation. Corneal nerve regeneration plays an important role in maintaining corneal health and function. In vivo confocal microscopy (IVCM) is the only non-invasive imaging technology that can observe corneal nerves. It has become a powerful technology to study the structure of corneal cells in health and diseases. It shows unique advantages in the diagnosis and clinical research of corneal diseases.Therefore, this paper will review the application of ivcm in the observation of HSK, especially the characteristic manifestations of corneal nerve, in order to further promote the application of confocal microscope in the diagnosis and treatment of HSK.