cis- and trans-Propylene oxide-1-d were synthesized from the corresponding propenyl halides via propenyllithium and propylene bromohydrin. Their NMR spectra (about 3% in benzene) were analyzed in terms of ABX3spin system and the assignment was carried out. The chemical shift of the methylene proton in cis position to the methyl group was found to be Δ = 1.86 ppm and that of the methylene proton in trans position Δ = 2.18 ppm (downfield from HMDS). The H-D couplings were observed in the methine-methylene part spectra decoupled from methyl protons. The observed JHD's agree with the theoretical relation: JHH= 6.5 14 X JHD.