Tricarbonylrhenium(I) and ‐technetium(I) halide (halide = Cl and Br) complexes of ligands derived from 4,5‐diazafluoren‐9‐one (df) and 1,10‐phenanthroline‐5,6‐dione (phen) derivatives of benzoic and 2‐hydroxybenzoic acid hydrazides have been prepared. The complexes have been characterized by elemental analysis, MS, IR, ¹H NMR and absorption and emission UV/Vis spectroscopic methods. The metal centres (Re^I and Tc^I) are coordinated through the nitrogen imine atoms and establish five‐membered chelate rings, whereas the hydrazone groups stand uncoordinated. The ¹H NMR spectra suggest the same behaviour in solution on the basis of only marginal variations in the chemical shifts of the hydrazine protons.