Glaucoma is a group of irreversible blind eye diseases with specific optic nerve damage and visual field defect.Early diagnosis and treatment of glaucoma is vital for prognosis, but difficult in clinical practice.Macular ganglion cell complex thickness(mGCC)consists of the inner three layers of retina:retinal nerve fiber, ganglion cell and inner plexiform layers, which is glaucoma target tissue so to be measured the thickness of the mGCC as better indicator for early diagnosis in glaucoma.Optical coherence tomography(OCT)is a non-contact, good repeatability technique to obtain fast high-resolution images from the anterior and posterior segments of the eye, and it has been widely used in ophthalmology.Spectral-domain(SD)OCT allows a higher image resolution and can measure the thickness of mGCC thickness, providing new parameters for the early diagnosis of glaucoma.