The Early Cretaceous Gucuo sandstones in southern Tibet are characterized by volcaniclastic litharenites. Petrography, geochemistry, provenance analysis show that volcanic grains of litharenites came from the volcanic rocks which show the character of intra-plate geotectonic setting in the area of the northern margin of the Indian Continent. During the Late Jurassic, quartzitic sandstones came from stable passive continental margin. Later, sandstones changed into a mixed source with the input of volcanic grains. The contents of volcanic grains increase upwards in the stratigraphic section, and become dominant during the Early Albian. Later, volcaniclastic sandstones stopped and were replaced by thick black shales. The provenance change of the Early Cretaceous sandstones were interpreted to the result of a contemporaneous volcanic event in the northern margin of the Indian Continent. This volcanic event was most probably related to the last break-up of the Indian Continent from the Australian-Antarctic continent during the Early Cretaceous.