A high temperature energy dispersive X-ray diffraction (EDXD) apparatus has been built using a vertical type goniometer, which makes it possible to measure the diffraction profiles of liquids up to 1873 K. The fundamentals of this apparatus were tested by obtaining the interference function of a SiO2 glass over Q=200 nm-1 at room temperature. The feasibility of this EDXD apparatus for high temperature liquids was confirmed by structural study of liquid bismuth germanate (Bi4Ge3O12) at 1373 K.