This study was designed to evaluate influence of oxidative stress environment on extrapituitary growth hormone (GH) secretion in the eye as well as to analize interdependence between eye GH levels and serum GH levels in normal and hypoxic conditions. 32 patients with developed proliferative diabetic retinopathy (PDR) represented oxidative stress model and were treated surgically by pars plana vitrectomy (PPV). 49 patients, non-diabetics in control group were selected from those who have not suffered from metabolic diseases and yet they had to be operated due to other ocular disorders. Vitreous samples were taken during PPV surgical procedure and simultaneously blood from the cubital vein was collected. Measurements of GH values in serum and vitreous samples were conducted by electrochemical luminescence assay (ECLIA). Evaluation of oxidathive stress was carried out using enzyme-linked immunosorbent assay (ELISA) of Advanced Oxidation Protein Products (AOPP) and Lipide Hydroperoxide (LPO) in serum and vitreous as well. Serum values of AOPP were significantly higher than vitreal in both groups (p<0,001 for each group), and for LPO only in PDR group (p<0,001). Significant positive correlation between serum and vitreous LPO values in diabetic group (r=0,909; p<0,001) was observed. GH values in both groups were significantly higher in serum, than vitreous (p<0,001 for each group) and comparing GH serum values between control and PDR group, significantly higher amounts were found in diabetics (p=0,012). Vitreous GH values measured in both groups were similar, slightly higher in diabetics. Results of our study have confirmed existence of GH secresion in the eye and disclosed that GH production in eye is autonomous and independent to pituitary GH and is also independent to oxidative stress influence.