Scanning tunneling microscopy has been used to investigate the molecular orientation of iron and cobalt naphthalocyanines (Ncs). FeNc molecules deposited onto NaCl at 250-degrees-C grew, in a squarelike pattern with a lattice spacing of approximately 1.5 nm; CoNc deposited under the same conditions showed a similar spacing of 1.5 nm, however, the structure was more columnlike. The difference in the structure is due to the orientation of the molecular planes. In the case of FeNc, the molecular planes are parallel to the NaCl substrate, whereas the CoNc molecules are lying perpendicular to the substrate.