Objectives: The Zhengyang Basin in Qianjiang, Chongqing is located in the wide spaced folds between southeastern Sichuan, Chongqing and northwestern Hunan Provinces. The Upper Cretaceous Zhengyang Formation that developed in the Zhengyang Basin is composed of two members. The first member is featured by alluvial and diluvial conglomerates, and the second member is featured by fluvial and lacustrine sandstones and siltstones, in which abundant dinosaur fossils were discovered. The basin is an intermountain basin formed the wide spaced fold belt since the Yanshanian Movement, and is ideal for studying of the Cretaceous regional tectonics of southeastern Sichuan. Detailed studies on this basin are lacking. Studies on the sedimentary sources and tectonic evolution of the basin is of great significance to reveal the Late Cretaceous tectonic evolution of southeastern Sichuan, as well as the living environment, death and mass burial mechanism of the contemporary dinosaur fauna. Methods: Based on observation, measurements and analyses on the sedimentary and structural characteristics of the Zhengyang Formation, we reevaluated the boundary fault, paleocurrent direction, sediment source and tectonic evolution history of the basin. Results: The conjugate shear joints in the basement of the basin show that the principal compressive stress σ1 is in the NW-SE direction, and the sedimentary source of of the Zhengyang Formation mainly came from the west. Conclusions: The remote effect of the Yanshanian subduction of the paleo-Pacific plate formed widely distributed joints and thrust faults in South China. Due to the continuous stress, these faults connected the detachment layers, thus the rock units stacked near the fault slope, and the anticlines spreaded and then gradually formed the wide spaced folds. In the late Yanshannian period, the normal fault "Abunjiang Fault" developed in this area with the retreat of the Pacific plate, which controlled the formation of the Zhengyang Basin with fault in the east and lapout in the west of the basin. The terrane on the west of the basin provided source materials. In the Himalayan period, this area was uplifted by local compression and denudation took place.