Purpose To evaluate the significance of axial length in case of branch retinal vein occlusion(BRVO). Methods A case-control study of axial length was performed using 34 patients with BRVO and 34 age and sex-matched control patients selected from a list of subjects who had undergone cataract extraction.Axial length measurement were taken with an A-scan ultrasonography. Results The affected and fellow eye in patinets of BRVO group did not differ statistically in axial length (P＞0.20).The mean axial length of affected eyes in BRVO group was （23.16plusmn;0.82）mm, and the mean axial length of control eyes was（23.78plusmn;1.06）mm.The difference in axial length between the eyes with BRVO and the eyes in the control group was not statistically significant(P＞0.10). Conclusion Hyperopia as measured by axial length is not a risk factor to BRVO. (Chin J Ocul Fundus Dis,1998,14:12-13)