Abstract: The eudialyte from Alaska is crimson and optically positive. Optical absorption spectra of the eudialyte are characterized by obvious absorption band at 530 nm and weak absorption band at 917 nm. Its physical properties, chemical composition and Mossbauer spectrum are similar to the crimson eudialyte from Kola peninsula in Russia and the deep Rose eudialyte from Fengcheng in Liaoning province. And its infrared spectrum is similar to that of the optically positive eudialyte. According to research of E. V. Pol′shin and Hanxueming, author thinks the colour of the eudialyte from Alaska is related to Fe2+ and Fe2+ in the eudialyte is mainly in a planar fourfold coordination.