Understanding how landscapes respond to abrupt climate change is essential for predicting future Earth system dynamics. While the erosional export of terrestrial sediment fundamentally shapes landscapes and builds stratigraphic records, the sensitivity of sediment-transfer systems to rapid, millennial-scale climate variability remains poorly constrained. Using a high-resolution record from Mangshan dated with 115 14C measurements, we reconstruct the Chinese Loess Plateau erosion and subsequent sediment transport by the Yellow River during the last glacial period. Our results demonstrate that both erosion and sediment delivery increased abruptly during short-term warm intervals. These sedimentation pulses align with Greenland Interstadials and strengthened East Asian summer monsoon phases, indicating that enhanced precipitation overwhelmed the stabilizing effect of glacial-period vegetation. This climate-erosion link is synchronously recorded in sedimentary sinks over 1300 km downstream, revealing a rapid source-to-sink signal linking high-latitude forcing to mid-latitude landscape evolution. Our results establish a precipitation-dominated erosion regime under the cold glacial background and underscore the high sensitivity of sediment flux to abrupt monsoon shifts, offering key insights for assessing future landscape responses to climate extremes.