Infrared spectra of Pu’er raw tea and Pu’er ripe tea were investigated using Fourier transform spectroscopy， in order to exploit a rapid method for discrimination of aging period for Pu’er tea samples. The results showed that the two kinds of Pu’er teas shared a similar woveform of infrared spectrum. However, due to the variations of aging time, leading to different chemical composition in pu’er teas, both Pu’er raw tea and ripe tea displayed corresponding different characteristic peaks. And the extent of aging of Pu’er tea had a significant relationship with optical density and waveforms of absorption peaks in the wave number range of 1 120～1 570 cm-1 and 400～853 cm-1, suggesting that the extent of aging of Pu’er tea may be identified by infrared spectrum technology rapidly and simply.