Abstract: In order to save the rare iceland crystal and increase the transmittance of polarizing prism, a polarizing prism made of iceland crystal and glass was designed. The design of the prism for superhigh transmittance of e beam with the Brewster incident angle was described. The sample was made of FK2 glass and iceland crystal, between which either glycerine or organic silica gel could be used for gluing. The theoretical analysis and experiment indicate that the transmittance of the prism is more than 96%, and the extinction ratio is better than 10-5. It was proved that the prism could replace the prism which was only made of iceland crystal in general.