The goal of the present study was to determine the true metabolizable energy corrected for nitrogen (TMEn) content, chemical compositions of the poultry by – product meal (PBPM), the relationship between their chemical compounds and TMEn in adult roosters. To examine the nutritional values of PBPM, a total of 30 fresh samples were collected from different slaughterhouses in the country. For TMEn estimation, each sample (25 g) was used to force feed to the 4 birds raised in individual metabolic cages. Dry matter (DM), gross energy (GE), crude fat (EE), crude protein (CP), ash and total volatile nitrogen (TVN) were measured according to standard methods. Average values for DM, EE, ash, CP, TVN and TMEn were obtained as 90. 05%, 22. 10%, 7. 50%, 60. 30%, 220 mgN/100g, and 3907 kcal/kg, respectively. There was a positive correlation between TMEn and EE, while the correlation between ash and TMEn was negative. Compared with EE and ash, the CP was less correlated (P<0. 05) with TMEn, while the TVN had no significant effect. The determined values of chemical composition and TMEn were used in fitting the simple regression equations, which can be in practice used to predict energy contents of PBPM samples in factory and production farms.