Infrared (IR) probes based on terminally blocked β-cyanamidoalanine 1 and p-cyanamidophenylalanine 2 were synthesized and the vibrational properties of their CN stretch mode were studied using FTIR and femtosecond IR pump−probe spectroscopies. Aromatic cyanamide 2 shows a complicated lineshape of the FTIR spectrum, which arises from the accidental Fermi resonance, and can be substantially simplified by deuteration of the cyanamide group. The transition dipole strengths of the cyanamide group are much larger than those of the nitrile group, but comparable to those of the isonitrile and azido groups. The vibrational lifetimes of the cyanamide group are similar to those of the nitrile and azido groups, but shorter than those of the isonitrile group. Cyanamide has the potential to be a good IR reporter of the conformational and environmental structure and dynamics of biomolecules in complementary to nitrile.