Abstract: 216 healthy Tilapia were randomly divided into six groups,and three replication were set within each group;the feed additives for the groups were broad bean alcohol extracts(No.1),broad bean ester extracts(No.2),broad bean acetone extracts(No.3),soy isoflavone(No.4),soy asaponin(No.5)and blank(No.6,basic diets as control) respectively.After 60days feeding with the experimental diets,effects of different feed additives on growth,feed conversion ratio and muscle quality of Tilapia were examined.The results showed no significant effect on growth performance(P>0.05),while the muscle quality analysis indicated that in the case of group 1and group 5,water content and protein content decreased and ash content increased slightly(P>0.05);but lipid content,collagen content and length of myofibril increased obviously(P<0.05),and drip loss decreased significantly(P<0.05).In conclusion,broad bean alcohol extracts and soy asaponin feed both embrittled the Tilapia muscle,and probably the asaponin ingredient from broad bean alcohol extracts played an important role in embrittlement.