Vibrational frequencies and approximate mode descriptions of 1,7-diaminoheptane (dahp) have been determined via Becke-3-Lee-Yang-Parr (B3LYP) density functional method with 6-31G(d) basis set. 'H, proton coupled and uncoupled 13C, I5N, DEPT, COSY, HETCOR, INADEQUATE NMR spectra and the magnitude of one bond 1Jch, 1-Ice coupling constants of dahp (C7H 18N2) have been reported for the first time. 1H, 13C, 15N NMR chemical shifts and J ch. 1Jcc coupling constants of dahp have been calculated by means of B3LYP density functional method with 6-311++G(d,p) basis set. Comparison between the experimental and the theoretical results indicates that density functional B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and NMR properties. © 2009 Chemical Society of Ethiopia.