Our study dealt with the material and technical aspects of newly discovered painted plaster fragments excavated from Xitou site in Xunyi County, Shaanxi Province (Xunyi is one of the earliest birthplaces of the Zhou Dynasties). A multi-technical approach was employed to identify the inorganic and organic materials in the painted plasters. The plaster layer and pigments were investigated by means of polarized light microscopy, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray diffraction (XRD) and Raman spectrometry. The results show that the pigments are iron-based ones (red and yellow ochre) and green earth. The plaster layer is mainly consisted of calcite, while a thin lime mortar forms the backing between the lime plaster coat and the painted layer in some samples. The adhesive ingredients were analyzed using gas chromatography-mass spectrometry (GC-MS). The results show that the binding materials on the painted plaster contain animal glue and perhaps egg. In addition, through comparison, it was found that the technique used for the painted plasters in Xunyi was similar to that used for other typical Chinese archaic murals. This study could help us explore the origin and history of murals in Guanzhong area during the pre-Zhou period.