Abstract: To study crystal chemical compositions ，mineral com binations, microfabric and vibrational spectrum of Hte Long Sein Jade from Myanmar, the EPMA，LRM and petrographic analytical testing techologies are employed in the research. The research indicates that Hte Long Sein Jade mainly consists of chromium rich jadeite, which occurs as mineral aggregate (> 75%). The crystal chemical formula of chromium-rich jadeite shows as （Na_0.830Ca_0.144）_0.974（Al_0.782Mg_0.156Fe_0.025Cr_0.053）_1.016〔Si_1.992O₆〕. The typical paragenetic mineral com binations are chromium-rich jadeite +astridite+jadeite+kosmochlor+ chromite. The internal feature of this jade is characterized by the stress deformational fibric. The LRS spectrum and the formative mechanism of Hte Long Sein Jade are discussed. The results show that Hte Long Sein Jade is similar to jadeite jade in crystal chemical compositions and vibrational spectrum, and can be called jadeite jade.