Abstract: Pathological ocular phypertension and larger diurnal fluctuation of intraocular pressure (IOP) are important risk factors of the progressive damages of glaucomatous vision field. In normal person, the IOP is fluctuant during 24 hours and the peak is in the early morning. The diurnal IOP fluctuation is associated with postures, eye perfusion pressure, axial lengths and so on. The IOP fluctuations is very important risk factors for the progressive damage of vision field in the patients with normaltension glaucoma, who usually showed abnormal IOP by 24hour intraocular monitoring and then can be  diagnosed and treated according to the curve of diurnal IOP. In primary open angle glaucoma patients, the regular pattern of the diurnal IOP fluctuation is similar to that of normal people, the pressure peak is also in the night, but diurnal IOP range is probably wider and the fluctuation of both eyes is obviously consistent. In chronic angleclosure glaucoma patients after laser peripheral iridotomy, the diurnal IOP fluctuation is larger, and positively associated with the baseline pressure and the degree of angle adhesion. Compared with laser and drugs, trabeculectomy is more advantageous to the longtime IOP and diurnal IOP fluctuation controlling. Prostaglandin analog is the best medicine choice for the controlling of the diurnal IOP fluctuations. (Int Rev Ophthalmol, 2013, 37: 388-391，396)