AIM: To evaluate the changes of retinal microvascular density in patients with sellar region tumor, and its correlation with the damage to visual field, and to explore its application value in evaluating optic nerve injury of those patients.METHODS: Cross-sectional study. A total of 157 patients(292 eyes)with sellar region tumor, including 82 cases(152 eyes)of pituitary adenoma and 75 cases(140 eyes)of craniopharyngioma, were selected from neurosurgery department and ophthalmology department of Beijing Tiantan Hospital, Capital Medical University between October 2018 and May 2022. A total of 90 people(180 eyes)during the same period, including the family members of patients, students and staff in Beijing Tiantan Hospital, Capital Medical University were collected as control group. All participants underwent optical coherence tomography angiography(OCTA)examination. The changes of retinal microvascular density and its correlation with visual field parameters were compared between the two groups.RESULTS: In patients with sellar region tumor, the radial peripapillary capillary(RPC)and superficial retinal capillary plexus(SRCP)density were significantly lower than that in the control group [50.81%(46.49%, 53.49%)vs. 52.78%(50.73%, 54.51%)and 50.57%(48.13%, 52.73%)vs. 51.63%(49.78%, 53.02%), all P<0.05]. The RPC density in the craniopharyngioma group was lower than that in the pituitary adenoma group [49.71%(44.33%, 53.14%)vs. 51.37%(47.42%, 53.95%), P<0.05]. The MD, PSD and VFI of the sellar region tumor group were -4.33(-12.22, -1.85)dB, 3.37(1.91, 8.82)dB and 92%(65%, 97%)respectively. RPC density of patients with sellar region tumor was positively correlated with MD and VFI, and was negatively correlated with PSD. The SRCP density of each quadrant was positively correlated with MD, and was positively correlated with VFI except Para-T and it was negatively correlated with PSD(all P<0.05).CONCLUSION: Retinal microvascular changes were present in patients with sellar region tumor. Lower vessel density indicates more severe damage to visual field. In the clinic, visual field examinations combined with OCTA were helpful to find the optic nerve injury of patients.