Abstract: Chemical weathering of silicates in large river basin has a significant effect on climate change and land-sea material exchange. How to decipher the chemical weathering history from river sedimentary archive has always been a challenge in the study on weathering processes at the Earth’s surface. Although the classical chemical weathering indices (CIA: Chemical Index of Alteration, WIP: Weathering Index of Parker, and so on.) have been well documented, how the weathering proxies in clastic sediments responds to climate change and its time scale remains controversial. As a world-class river originating from the Qinghai-Tibet Plateau and with its basin significantly influenced by the monsoon, the Changjiang (Yangtze) River is a natural laboratory for studying the transmission of weathering proxies among the large basin and the interrelationship of climate, weathering, and sedimentation. Therefore, we examined the changes of different weathering proxies in the river basin since the Holocene by using the sedimentary records from the middle reaches, estuary, and the inner shelf of the East China Sea. The bulk samples, ＜63 μm fractions, and ＜2 μm fractions (clay) show that fine-grained sediments (clay/suspended particulate matter) could carry stronger weathering proxies than coarse-grained ones (bulk samples/floodplain sediments). The classical weathering proxies indicate that the integrated weathering intensity of large basins, and even the CIA in the clays could not reflect the temperature change on millennial scale but the provenance changes that related to rainfall migration and human activities. This study revealed the complexity of weathering-climate responses and feedbacks from large river basins. Therefore, interpretation on weathering proxies in clastic sedimentary archives shall be cautious.