The present study is carried out for the identification of clay minerals of the Bara Formation exposed at Ranikot section, Lakhra section and in subsurface core samples of SB-14 and ST-24 bore holes drilled in the Thar Coalfield. Scanning electron microscope and X-ray diffraction (XRD) techniques reveal that the mineral kaolinite exists as spheroidal, stacks, thin idiomorphic plates and fragments. Additionally, chlorite (Mg-rich, Fe-rich), illite and smectite were identified under scanning electron microscope (SEM). The XRD investigation showed the presence of kaolinite, chlorite, random mixed clay layer, illite-montmorillonite, potassium feldspars, quartz, calcite and gypsum. The presence of identified clay minerals indicate that the Bara Formation was deposited under the fluvio-deltaic depositional conditions and their source rocks were potentially the eroding igneous and metamorphic rocks.