Feeding Experiments were designed to measure the growth of grass carp fingerlingswhen fed with different proportions of enzymatic fiber meal containing 10--12% crudeprotein, mixed with other ingredients. Fiber was obtained from the waste of the sugarand paper manufacture industries. Experiments on food nutrition of fingerlings werereplicated three times in six suspended 14 M² netcages, each stocked with 500--700 fin-gerlings, their weight ranging 2. 42--9. 90 gm. Results indicated that feeds containing60% enzymatic fiber could substitute for the cereals which had been used by the tradi-tional technique as staple food in fingering culture. Field experiments were conducted inthre 666 M³earthen ponds, each stocked with 3000 grass carp fingerlings for a periodof 103 days. The pellet, composed of 60% enzymatic fiber and other ingredients andcontaining 19. 15% crude protein level, yielded a 61. 8--116% increase in productionand saved 70% cereals as compared with the results secured in the control ponds in whichfingerlings were fed solely with cereals. Pellets of the same composition were used in anarea of 119 mu(1 mu = 666M²)to feed commercial-sized fishes,their weight averaging 500gm. The daily feed allowance approximated 1--2% the weight of the fish. The total fishyield after eight months was 62% higher than that of the previous year. Pdrotein requirements of the grass carp fingerlings: (1) the optimal protein level ofthe diet, determined by both methods of polynominal regression and parabolic curve,was found to be 22.77--27.66%. The protein effciency ratio decreased with the in-crease in protein content of the diet according to the formula, Y= 29.2786 -- 0. 52968 X;(2) carcass analyses by the paper-chromatography method revealed 18 amino acids.Growth proved to be satisfactory when the composition of the pellet diet contained theessential amino acids. The growth rate exhibited a negative relation with the content ofcellulose in the diet.