Archaeological studies indicated that the “Baihuimian” building material has been excavated widely in the Neolithic Age, which was not only hard, but also of beauty and cleanly. Archaeologist concluded that the “Baihuimian” may be the earliest man-made-lime in China. So, the infrared spectroscopy was used to analyze the “Baihuimian” and “Baitiaoshi” from Taosi site. The results indicated that the ratio of ν2 to ν4 is markedly different between “Baihuimian” and “Baitiaoshi” by infrared spectroscopy which shows that there is a big difference in the disorder parameter of calcium carbonate crystal, suggesting calcined “Baihuimian” is identified depending on infrared spectroscopy. Thereby, it offers a simpler and more efficient method to study the origin of lime. Meanwhile, the temper of “Baihuimian” was also analyzed by microscope and infrared spectroscopy methods, respectively, which proves that the mixed materials (admixture) in “Baihuimian” is cellulose.