Structurai analysis of Li2O·14Nb2O5 has been carried out by combined convergent-beam electron diffraction (CBED) and high resolution electron microscopy (HREM) in an analytical electron microscope with a point resolution of 0.4 nm. The space group C2/m is confirmed by CBED. HREM structure image shows that Li2O·14Nb2O5 is made up of 4×4 blocks of oxygen octahedrons The 3×3 channels within the 4×4 blocks and the metal atoms at the centres of the octahedrons which are 0.38 nm apart are clearly resolved. Combined CBED and HREM for structural analysis is an important development in electron crystallography.