The consumption of atmospheric CO2 through continental weathering played a critical role in shaping the evolution of the late Paleozoic Ice Age (LPIA), presumably driven by the Hercynian orogeny and the evolution of terrestrial plants. However, the relative impacts of these two major drivers to continental weathering remain poorly constrained. The South China Block was located near the paleo-equator under a relatively stable tectonic setting during the late Paleozoic, and therefore provides valuable insights into silicate weathering dynamics. Here, we report a 60-Myr-long record of the chemical index of alteration (CIA) from a continuously deposited slope succession in South China. By integrating existing records of weathering proxies, we concluded that the Hercynian orogeny played an overwhelming role in enhanced silicate weathering rates during 333-291 Ma, whereas paleotropical forest ecosystems demonstrated their significant influences on weathering patterns during their rapid expansion phase (333-316 Ma).