The aims of the present work are to prove the possibility of employing IR spectra to investigate the compounds obtained by interaction of Squaric acid (H 2 Sq) and phenyl- or alkyl glycidyl ethers (PhGE or AlkGE), to establish the most suitable absorbances for quantitative analyses and to evaluate the formation of H-bonds. Indication of H-bond formation could be taken as the shift of some characteristic absorption bands Δν for (C-O-C) groups and decreasing of the value Δh 1 / 2 , where Δh 1 / 2 is the peak width at half height. The interactions of H 2 Sq and glycidyl ethers were made in the medium of the ethers.