Transforming growth factor-β (TGF-β) genes considered as one of the large family of multifunctional growth factors that participate in the regulation of a broad range of biological processes in chicken. The current study was conducted to determine genetic polymorphisms of TGF-β2 gene by using PCR-RFLP method in Giza M-2 line which selected for high 6- week live body weight (LBW) for seven generations compared to random bred control (RBC) line. Also, the association between TGF-β2 with productive performance was evaluated for each line. Results indicated that, Giza M-2 line had higher LBW at different ages, LBW at 6 week of age (LBW6), and carcass parts weights and percentages compared to RBC line. In addition, Giza M-2 line had high TGF-β2-BB genotype frequency value (0.80) which explains the positive effects of TGF-β2 gene on LBW and carcass traits in Giza M-2 line compared to RBC line. The current result conducts the broad significant effects of TGF-β2 gene on productive performance of chickens. In addition, the association between these valuable productive traits and TGF β2 gene will effectively develop the selection process by using Marker-Assisted Selection (MAS) in Giza M-2 line breeding program in the near future.