High-resolution spectra of molecular vibrations in metformin, one of the most widely used antidiabetic drugs, which also possesses antiaging and antitumor properties, have been obtained by a high-sensitivity Raman-scattering technique. It is established that rather narrow (4–10 cm^–1) spectral lines observed in a 300–1200 cm^–1 range can be used for separating spectral components corresponding to the vibrations of particular functional groups. This circumstance makes metformin an interesting model for studying molecular biosensors.