The electronic transport properties of molecular junctions constructed by the five-membered heteraromatic molecules -thiophene-1,4-dithiol, pyrrole-1,4-dithiol and furan-1,4-dithiol-in contact with gold electrodes have been calculated by applying the elastic scattering Green's function theory approach in combination with the hybrid density-functional theory without using any fitting parameters. It shows that the molecule with thiophene has similar conductivity as that with benzene-1,4-dithiol. The ordering of the five-membered heteraromatic molecules in terms of conductivity is thiophene > pyrrole > furan. (C) 2003 Elsevier Science B.V. All rights reserved.