Objective:To study the effect of nattokinase on visual functions in rabbit eyes with central retinal vein occlusion(CRVO). Methods:Central retinal vein occlusion of rabbit model was established with argon laser photocoagulation to retinal vein. After laser,intravitreal injections of either 0.1 ml of 0.1 FU nattokinase,or Ringer’s solution(negative contro1)were given once daily for three days. And the group C as control was not given any treatment. Before and 14 days after laser,flash electroretinogram(FERG)was recorded and statistically analyzed. Results:Argon laser photocoagulation induced an experimental model of central retinal vein occlusion. Statistically significant difference existed in latencies of FERG-a and FERG-b among the groups(P < 0.05). Conclusion:An experimental model of central retinal vein occlusion was successfully produced in rabbit by argon laser photocoagulation. Nattokinase can ameliorate visual functions.