Three different methods were used to determine and compare between and gross energy content of feed, fish-edible parts and faecal samples. Method 1: the GE content was determined from the data of the actual chemical composition and the caloric values of the energy bearing nutrients; viz 5.65, 9.45 and 4.15 Kcal /g for protein, fat and carbohydrate, respectively. Method 2: the GE content was determined by combustion of the concerned materials in bomb calorimeter. Mcthod 3: the GE content was determined by dichromate wet oxidation. The results indicated that combustion is the most acurate method for determination of GE content of the three tested materials. Calculation using chemical composition and determination by wet dichromate oxidation underestimated the GE content. Justification of the results could be reached by using a factor 1.02-1.05; with an average of 1.035 for appropriation and simplification. Further investigations are, however, required for a greater level of accuracy of the assigned factor.