Hybrid crucian carp was obtained by crossing Carassius auratus auratus (?) withC. auratus cuvieri (?), and temperarily named Gaoyou hybrid crucian carp. This paper reports theresults of the systematic studies on its growth, biological characters, including growth, feeding pat-terns, egg development and genetic characters. The average individual and group weight increaseof one-year-old Gaoyou hybrid crucian carp are greater than its parents by 101% and 99.6%respectively. The values of the two-year-old Gaoyou hybrid crucian carp are 90.5% and 97.8%respectively. The Gaoyou hybrid crucian carp has several other merits, such as high quality meat,high meat contents, strong resistance to disease and adversary conditions, convenience in fry pro-duction and high economic benefit. So far, up to 6,500,000 fry of this fish have been cultured in 9counties of Yangzhou suburb and remarkable social and economic benefits have been achieved.