In order to obtain Carassius auratus with green fluorescence, the plasmid GFP gene was transferred into the fertilized eggs by microinjection. The results showed that the three batches of fertilized eggs (4310,3952, 4056) hatched 543?282 and 266 fry, respectively, and the survival rates were 17.02%?12.53% and 13.52%, respectively; there were 23?24 and 18 fry with green fluorescence, respectively, and the expression rates were 4.24% ?8.51% and 6.77%, respectively. The detection of green fluorescence indicated that GFP gene begins to express in the muscular effect stage of gold fish embryos.