A 670-cm-long sediment core from Lake Liangshanpo, a waterbody used to connect to the Yellow River, was analyzed to understand environmental changes in the lower reaches of Yellow River area during the late Holocene. Based on AMS-¹⁴C dating and the integration of high-resolution multi-proxy records such as grain size, magnetic susceptibility, total organic carbon, and C/N as well as historical documents, we infer that the lake has experienced five distinct phases of environment evolution during the last 1200 years. Our results show that a low lake-level stand with a wetland environment prevailed during 790-940 AD under dry and cold climate conditions. Then during 940-1215 AD, the lake expanded and reached to the maximum depth due to the flooding of the lower Yellow River (LYR) under relatively warm and wet climate conditions. In 1215-1310 AD, the lake began siltation likely due to the southward displacement of the Yellow River, experienced rapidly shrunk and a wetland environment. During 1310-1470 AD, the lake expanded due to the flooding of the LYR again, albeit the area is smaller than that of the maximum phase. From AD 1470 to the present, rapid siltation corresponding to the further southward displacement of the Yellow River especially in 1494 AD and until 1855 AD flooding events occurred when the channel of the LYR shifted back and the river discharged to the Bohai Bay. In sum, under the background of climate change, the avulsion and levee breaches of the LYR are the major reason for the environmental evolution of Lake Liangshanpo.