Highlights • Subject identification by hand odor using GCxGC-MS and Bayesian testing is proposed. • Bayesian testing enables to decide if two odor samples stem from the same person. • The AUC, sensitivity and sensitivity of the classifiers is evaluated on a panel of 139 subjects. Abstract A new method for identifying people by their odor is proposed. In this approach, subjects are characterized by a GCxGC-MS chromatogram of a sample of their hand odor. The method is based on the definition of a distance between odor chromatograms and the application of Bayesian hypothesis testing. Using a calibration panel of subjects for whom several odor chromatograms are available, the densities of the distance between chromatograms of the same person, and between chromatograms of different persons are estimated. Given the distance between a reference and a query chromatogram, the Bayesian framework provides an estimate of the probability that the corresponding two odor samples come from the same person. We tested the method on a panel that is fully independent from the calibration panel, with promising results for forensic applications. 2 Keywords Bayesian inference, comprehensive two-dimensional gas chromatography, forensics, human hand odor, mass spectrometry.