The glass formation area in the ternary ZnO-CdO-TeO2 was investigated at 1200 deg C by melting 33 different compositions. Only a narrow zone of the ternary composition system gives rise to transparent, opalescent and partly crystallised glasses. All these glassy materials were obtained by using a conventional melt quenching method after melting in platinum crucibles. The glassy materials were studied by optical absorption, X-ray diffraction (XRD) and infrared, as well as by Raman spectroscopies. The XRD diagrams for transparent samples showed a fully amorphous structure, while for opalescent and partly crystallised samples, some well defined diffraction peaks appear, and correspond to the crystalline phases: CdTe, CdtEO3, ZnO and ZnTeO3.