To analyze the main mineral composition of the newly found clay minerals in Chuxiong, Yunnan and to determine whether the major minerals are attapulgite clay, this paper conducts tests and researches with infrared spectrum and X-ray fluorescence spectrum on the five kinds of the newly found clay samples. In terms of the infrared spectrum of five samples, the absorption band at 3 437 cm-1 is the hydroxyl vibration caused by the water of crystallization in attapulgite clay, the absorption band at 3 651 and 3 621 cm-1 is symmetric and asymmetric stretching vibration caused by the hydroxyl of the structure water connected with Mg, Al octahedral on the edge of the hole of attapulgite clay; The absorption peak at 3 699 cm-1 is hydroxyl stretching vibration with internal structure between the tetrahedral and octahedral structure of Mg, Al connected; absorption peak at 1 633 cm-1 is the hydroxyl bending vibration absorption peak of the structure and absorption water, Absorption peak at 1 010 cm-1 is the bond’s (Si—O)characteristic peak of covalent bond (Si—O—Al), Absorption peak at 913 cm-1 is dioctahedral hydroxyl (Al2OH) deformation of the vibration characteristic absorption peak, near the absorption band at 536 and 536 cm-1 is the bond’s (O—Si)characteristic peak of covalent bond (Si—O—Si). The experiments showed that clay minerals of five samples contain higher composition of attapulgite clay, It is found that infrared spectra of three black sample ware compare with spectrum of attapulgite clay similarity in more than 93%, three black samples containing composition of attapulgite clay is very high; the five kinds of attapulgite clay samples may be attapulgite clay minerals. The attapulgite clay formula of attapulgite clay samples is mainly Al5Si8O20(OH2)4·4H2O.