A apparatus for estimating concentration may include: a spectrum obtainer configured to obtain Raman spectra of an object; and a processor configured to extract, from the Raman spectra, at least one analyte spectrum related to an analyte and at least one non-analyte spectrum related to a biological component other than the analyte, and estimate concentration of the analyte based on a first area under a curve of the at least one analyte spectrum and a second area under a curve of the at least one non-analyte spectrum.