Abstract: Xichuan Basin, located in the southwest of Henan Province, is an elongated basin with its longitudinal axis oriented in the northwest— southeast direction. The "red— beds " unconformably deposited on the Precambrian or Cambrian rocks are widely distributed in the basin, with a maximum thickness of over 1600m. In 1974, Upper Cretaceous dinosaur eggs were first discovered in these beds by the Twelfth Brigade, Bureau of Geology and Mineral Resources of Henan, and the egg—bearing beds were divided into three formations: Gaogou, Majiacun, and Sigou formations. After this discovery, the latter author surveyed the area, and collected two clutches of eggs and many eggshell fragments in 1975. Two years later, the Twelfth Geological Brigade collected many eggshell fragments from 9 localities (fig. l). In this paper, we characterize the dinosaur eggshell assemblages from 10 localities in the Xichuan Basin and discuss the ages of the egg—bearing beds.