Intravitreal fibrin clots were produced by intravitreal injection of 0.2 ml autologous plasma in 18 rabbit eyes. Subsequently these eyes were treated by intravitreal injection of either tissue plasminogin activator(t-PA) or saline. In the t-PA(12.5mu;g) group(n=10),intravitreal fibrin clots of 6 eyes cleared up within 6 hours, and that of the other 4 eyes within 1 day. In the saline group( n=7), the complete clearallce was not seen after 7 days. The difference of time between two groups was significant ( P＜0. 05), and no evidence of toxic effect was observed as measured by slit-lamp biomicrocopy, ERG, light microcopy and transmission electron microscopy.One eye treated with 100mu;g t-PA also resulted in a total clearance within 6 hours,but retinal toxicity was demonstrated with ophthalmoscopy and light microscopy. （Chin J Ocul Fundus Dis,1994,10:14-16）