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Speleothem δ¹³C in monsoonal China differs from speleothem δ¹⁸O, which is widely used as a climatic proxy for several complex control reasons. Nevertheless, δ¹³C records have the potential to reveal the implications of hydroclimatic changes. This study reports a speleothem δ¹³C record from Didonghe (DDH) Cave in central China spanning 34 to 13 kyr BP. After we investigated the factors that influence speleothem δ¹³C, we found that the δ¹³C record showed that DDH Cave can prompt directional shifts via local hydroclimatic changes, such as in vegetation types, biomass, and rock–water interaction processes, suggesting that δ¹³C is mainly controlled by the local hydroclimate. Ensemble empirical mode decomposition (EEMD) results revealed a coupling relationship between δ¹⁸O and δ¹³C on multiple timescales, which suggested that changes in precipitation caused by large-scale monsoonal circulation are controlled by regional hydrological conditions to a great extent. However, the hydrological conditions of the cave were relatively mild and humid during the last glacial maximum (LGM), which revealed the impact of evaporation on changes in the region’s hydrological conditions. We also found that the δ¹⁸O and δ¹³C profiles decoupled when δ¹³C changed with a shift in the location of the westerly during HS1. The δ¹³C record correlates well with other paleoclimate records, suggesting that regional hydrological conditions are also modulated by the Earth’s internal and external driving factors.