This paper deals with the effects of protien and carbohydrate contents in feedson the growth of black carp (Mylopharyngodon piceus) fingerlings. The experimentalfeeds were composed of casein, dextrin,fish-liver oil, powder of carboxymethylcellulose, mix-mineral and suitable amount of vitamins. The black carp fingerlingsused in the experiment were 37.12--48.32 grams in average weight, and rearedunder water temperature of 24--34℃ for eight weeks.Computing by straight--line regression and parabolic regression indicates that theoptimal proportion of protien in the feed should be 29.54--40.85%. The interactionbetween protien and carbohydrate is obvious. When the fingerling were given with afeed containing 37--43.3% of protien and 9.5--18.6% of carbohydrate, the fishgrow very fast. Therefore, the content of carbohydrate in the feed for black carpfingerlings about 20% seems to be suitable.The protien content in feed directly affects the content of protien, fat and car-bohydrate in fish body and the liver. The liver starch of fish is increseased with the increase of carbohydrate content in the feed.The digestive rate of protien in black carp fingerlirgs is affected by the quantityof carbohydrate contents in the feed. When carbohydrate content below 30% in feed,the protien digestive rate can be kept at 92%; while the carbohydrate content wasincreased to 43%, the protien disgestive rate will be greatly decreased. The reason ofit may be that black carp is carnivorous.The hemoglobin of black carp fingerlings was measured. Except the starvedgroup is 5 g hem./100 ml all the rest groups are 5.8--6.5g hem./100ml. It is believedthat the composition of feed makes little effect on hemoglobin level of black carpfingerlings.