The first eleven vertical ionization energies of mono and diethynylfurans have been calculated using various electron propagator decouplings. Among all ethynylfurans, the pi-orbital interactions between ethynyl and furan moieties are found to be strongest in 2,5-diethynylfuran. Oxygen atom of the furan ring and carbon atoms of ethyne group play important role in stabilization/destabilization of HOMO/LUMO of ethynylfurans. Our results for energetic stability, dipole moment, HOMO-LUMO gap, ionization energies, and electron affinity indicate that 2-ethynylfuran among monoethynylfurans and 2,5-diethynylfuran among ethynylfurans may be useful precursors for the preparation of conducting polymers.