Superconductivity of Nb2AlC has been previously reported, but the origin is not clear. In this paper, in situ Raman spectra of Nb2AlC are measured in the temperature range from 80 to 380 K at ambient pressure. The line-width of E2g (ω1) mode increases with temperature which originates from the anharmonic phonon–phonon scattering. On the contrary the line-widths of E2g (ω2) and A1g (ω4) modes decrease continuously at elevated temperature. The phenomenon is explained by the electron–phonon coupling. The origin of superconductivity is therefore interpreted by the coupling of Nb 4d electrons with E2g (ω2) and A1g (ω4) phonon modes. Copyright © 2013 John Wiley & Sons, Ltd.