Purpose <p>In postmortem ethanol analysis in decomposed cases, simultaneously detected volatile organic compounds (VOCs) serve as indicators of postmortem ethanol production. Among these, 1‑propanol is the most widely used marker; however, it is sometimes absent even in markedly decomposed bodies, thus making interpretation difficult. This study aimed to comprehensively detect postmortem VOCs in femoral muscle samples collected at autopsy and to re-evaluate indicators of postmortem ethanol production.</p> Methods <p>Among consecutive autopsy cases from a single institution, those involving antemortem intake of substances or pathological conditions that could increase VOCs were excluded. The cases were classified according to the degree of external decomposition. Femoral muscle samples were analyzed using headspace gas chromatography–mass spectrometry, and the detection profiles of VOCs and their relationship with ethanol were examined.</p> Results <p>Twenty-eight VOCs were identified in the femoral muscle, and both the detection frequency and number of detected compounds increased with the progression of decomposition. Among the major compounds detected, isovaleraldehyde, butyric acid, and 1-propanol showed weak correlations with ethanol. Ethanol was also detected in cases where these compounds were present. Contrastingly, all of these compounds were sometimes absent even in the markedly decomposed cases, indicating their limitations when used as single indicators.</p> Conclusions <p>This study elucidated the characteristics of VOCs produced postmortem in the femoral muscle and demonstrated both the utility and limitations of indicators for evaluating postmortem ethanol production. These findings provide fundamental data that may improve the reliability of ethanol interpretation in autopsies.</p>