A meridic diet (Ceratitis capitata #1) containing corncob as a bulking agent was developed and found comparable to diets currently used for rearing the larvae of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann). The composition of C. capitata #1 diet (mg/50 g diet) is essential amino acids 636; arginine, 106.8; histidine, 45.6; isoleucine, 56.4; leucine, 108; lysine, 58.8; methionine, 27.6; phenylalanine, 70.8; threonine, 54; tryptophan, 28.8; valine, 79.2; non-essential amino acids 964.8; alanine, 78; aspartic acid, 112.8; cystine, 40.8; glutamic acid, 392.4; glycine, 90; proline, 124.8; serine, 78; tyrosine, 48; ribonucleic acid, 100; vitamins, 5.35; (thiamine [vitamin B₁], 1.0; riboflavin [vitamin B₂], 1.0; nicotinic acid, 1.0; pantothenic acid, 1.0; pyridoxine [vitamin B₆], 1.0; biotin, 0.1; folic acid, 0.25); anti-microbials, 256 (methylparaben), 100; sodium benzoate, 100; p-amino benzoic acid, 1.0; streptomycin, 50; oxytetracycline, HCl 5; cholesterol, 40; inositol, 10; choline chloride, 20; minerals (McCollum and Davis Salt mixture No. 185), 100; citric acid (acidulant), 500; sucrose, 2000; corncob grit (screen size 30/80), 12,000; distilled water, 33,000 and pH 3.5. The omission of all 10 essential amino acids from the meridic diet mixture inhibited development past the first instar. Deletion of eight non-essential amino acids, 10 vitamins, sugar, or ribonucleic acid delayed larval growth. In addition, larvae reared on diet without non-essential amino acids, vitamins, sugar or cholesterol resulted in pupal weight loss. Pupal recovery and adult emergence were affected by the removal of 10 vitamins or cholesterol from the C. capitata #1 diet. Flight ability was decreased in the absence of 10 vitamins. No significant effects were shown in diet lacking salt mixture.