Using such means as ICP-MS, IC, XRD and IR, this paper has systematically studied the compositions of Chinese pearls and their shells characterized by different geneses or different localities. Some conclusions can be reached: ① Freshwater cultured pearls contain relatively rich P, Mn and Ba, whereas sea-cultured pearls have comparatively abundant Sr, Zn, Cr and Ni. ② Compared with freshwater cultured pearls, sea-cultured pearls have more varieties and higher content of cations and anions as well as higher content and level of amino acid. ③ There exist consistent compositional variations between sea-cultured pearls and their shells or between freshwater cultured pearls and their shells. Nevertheless, there are obvious compositional differences between the nacres and the pearl cores of sea-cultured pearls. These results can play a certain role in identification and theoretical-pharmacological researches of pearls.