AIM: To analyse the characteristic of macular microcirculation and structural features detected by optical coherence tomography angiography(OCTA)in retinal branch vein occlusion(BRVO), and analyse the risk factors of visual acuity(VA).METHODS: Eligible eyes from subjects(92 with BRVO and 38 healthy people)were included. The relationship between factors and VA was analyzed by retrospective. Vessel density affected by vein occlusion of 3×3mm2 centered on the fovea(3×3mm VD)and foveal vessel density(foveal VD)in the superficial capillary plexus(SCP)and deep capillary plexus(DCP), were measured by OCTA. Central macular thickness(CMT), neuroepithelial layer thickness and height of subcortical fluid in patients with BRVO were measured.RESULTS: The DCP, SCP, FD300, density of superficial fovea, density of superficial fovea and AI of the BRVO group were significantly different with control group(P<0.01). Multivariate regression: Age(P=0.033, OR=1.152, 95%CI=1.011-1.312). Density of superficial fovea(P=0.010, OR=1.260, 95%CI=1.056-1.504)and Macular fovea thickness(P<0.01, OR=1.033, 95%CI=1.021-1.045)were risk factors of VA. DCP and SCP were negatively related with CMT and neuroepithelial layer(P<0.01). CMT was positively correlated with the thickness of neuroepithelial layer and the height of subcortical fluid(P<0.01).CONCLUSION: Using OCTA, we can observe the BRVO retinal blood flow and the changes of the structure of the retinal section, and the pathological features of macular retina in BRVO patients can be observed more comprehensively. Age, density of superficial fovea and macular fovea thickness were risk factors of VA.