Penelitian ini bertujuan menganalisis pengaruh pemberian pakan dari sumber protein yang berbeda terhadap rasio efesiensi protein, retensi protein, pertumbuhan, sintasan dan FCR benih ikan kakap putih. Hasil penelitian menunjukkan bahwa rasio efesiensi protein tertinggi pada perlakuan C (tepung testis sapi) sebesar 2,33%, disusul perlakuan B (tepung ikan) sebesar 1,81% dan perlakuan A (tepung kedelai) sebesar 1,66%. retensi protein tertinggi pada perlakuan C (tepung testis sapi) sebesar 1,89%, disusul perlakuan B (tepung ikan) sebesar 1,85% dan perlakuan A (tepung kedelai) sebesar 1,77%. Pertumbuhan harian tertinggi pada perlakuan C (tepung testis sapi) sebesar 0,22%, disusul perlakuan B (tepung ikan) sebesar 0,17% dan perlakuan A (tepung kedelai) sebesar 0,15%. Pertumbuhan mutlak tertinggi pada perlakuan C (tepung testis sapi) sebesar 2,21 gram, disusul perlakuan B (tepung ikan) sebesar 1,69-gram dan perlakuan A (tepung kedelai) sebesar 1,53 gram. Sintasan tertinggi pada perlakuan C (tepung testis sapi) sebesar 94,44%, disusul perlakuan B (tepung ikan) sebesar 91,11% dan perlakuan A (tepung kedelai) sebesar 87,78% gram. FCR terbaik pada perlakuan C (tepung testis sapi) sebesar 1,88%, disusul perlakuan A (tepung kedelai) sebesar 2,04% dan perlakuan B (tepung ikan) sebesar 2,05% dan kualitas air masih berada pada kisaran optimal untuk pemeliharaan benih ikan kakap putih. This research aimed to analyse the influence of feeding different protein source on protein efficiency ratio, protein retention, growth, survival and FCR of white seabass seeds. The result showed that the highest protein efficiency ration in treatment C (cow testicle meal) of of 2.33%, followed by treatment B (fish meal) at 1.81% and treatment A (soybean flour) at 1.66%. The highest protein retention was in treatment C (cow testicle meal) of 1.89%, followed by treatment B (fish meal) of 1.85% and treatment A (soybean flour) of 1.77%. The highest daily growth was in treatment C (cow testicle meal) of 0.22%, followed by treatment B (fish meal) of 0.17% and treatment A (soybean flour) of 0.15%. The highest absolute growth was in treatment C (cow testicle meal) at 2.21 grams, followed by treatment B (fish meal) at 1.69 grams and treatment A (soybean flour) at 1.53 grams. The highest survival rate was in treatment C (cow testicle meal) of 94.44%, followed by treatment B (fish meal) of 91.11% and treatment A (soybean flour) of 87.78% gram. The best FCR was in treatment C (cow testicle meal) at 1.88%, followed by treatment A (soy flour) at 2.04% and treatment B (fish meal) of 2.05% and water quality was still in the optimal range for the rearing white seabass seeds.