Introduction:  Hyperglycemia is a consequence of uncontrolled diabetes and over a long period of time can lead to serious violations of the various systems of the body. In daily clinical practice, glucose level in blood and glycated hemoglobin are major and frequently used worldwide laboratory findings for the diagnosis of glucose metabolism disorders. In forensic medicine, the diagnostic value of post-mortem blood glucose levels is questionable because of its significant and rapid variation after death. Our research was aimed to analyse glucose concentration in blood after death and to estimate its diagnostic value. Methods: Data analysis of the State Forensic Medicine Service (SFMS) of Vilnius region of sudden death cases was performed. 238 autopsy findings were analysed. A retrospective analysis was performed using the R commander program. Results: The analysis included 238 individuals, 161 (67.6%) were men and 77 (32.4%) women. Mean age was 52.28 ± 15.45 yeras. Mean  alcohol level in blood was 2.257 ± 1.482 g/L. Mean post-mortem glucose concentration in blood was 6.716 ± 5.800 mmol/l. The lowest glucose concentration was 0.600 mmol/l and the highest - 33.300 mmol/l. There were no significant glycemia level difference between men and women (p = 0.279). In 6 cases, glucose concentrations were compared before and after death. The difference in blood glucose was insignificant (p = 0.90). There was no strong correlation between ethyl alcohol and glucose concentration (r = 0.037, p = 0.667). There was a weak correlation between age and blood glucose concentration (r = 0.03, p = 0.639). Conclusions: According to SFMS autopsy data, post-mortem glucose levels remain within the normal values. Evaluation of glucose after death remains a valuable diagnostic criterion for sudden death due to hyperglycaemia, when the hyperglycaemic episode is first and fatal to the subject.