Spectrum analysis of eleven N-cycloalkyl amides reveal that three of these, N-cyclopropyl formamide, N-cyclobutyl formamide, and N-cyclopentyl formamide, exist both in the E and Z configurations about the central C-N bond. In the cases of N-cyclohexyl formamide and N-cycloheptyl formamide, the amide moeity did not show the double bond character because of deviation from co-planer.