Chemical components, structure and thermal faces of nephrite from Jilin Province were studied by means of electron probe, X-ray powder diffract ion (XRD) and differential thermal analysis (DTA). Nephrite was determined by chemical components and spectrum of X-ray powder diffraction of the jade. (OH)^- was dehydrated from tremolite together with the production of new minerals when the minerals were heated to 874℃. The color of nephrite is white, and the data of its hardness, density and refractive index coincide with data of nephrite from Xinjiang.