The application of carbon isotope (δ13C) collected from stalagmite to reconstruct the past climate and/or ecologic evolution, relative to other preserved indicators, is much limited due to its complex influencing factors including climate outside cave and complicated and site-specific karstic process. In terms of various climate and non-climate limiting factors on stalagmite δ13C, and combined with a large number of geological records and modern cave monitoring data of the latest researches, the pathway and behavior of the signal transmission of δ13C in the cave system were analyzed. The possible relationship between δ13C excursions and climate oscillations under different time scales was thus discussed. Although the degree of noise becomes increasing mixed with δ13C on centennial scales or shorter, the climatic elements, such as temperature and humidity (or precipitation), as predominant modulators exert directly or indirectly influence on vegetation overlying the soil and associated soil CO2 productivity on millennial-orbital scales. Future work should be focused on further deeply extracting the common δ13C signals from specific caves by exploring the controlling factors, both including climatic and non-climatic ones, attaching importance to the seasonal characteristics of stalagmite δ13C, and taking full advantage of its potential in the indication of local environmental events. The use of multi-proxy and multi-method will contribute to better understanding the interesting linkages among the δ13C characteristics, karstic process, global carbon cycle and associated climate change.