Three stalagmites, collected from three caves which are located very close to the border district of Guilin city, Guangxi in China, had ²¹⁰ Pb test. The climatic conditions, geological background and ecological environment of the three caves are similar. 25 effective data were obtained from these tests. Fifteen valid date were obtained. Moreover, the laminaes of the three stalagmites are densified, homogeneous, presenting regular repeatability, but without obvious hiatus, and there was dripping water above the stalagmites when samples were collected. Furthermore, the closed conditions, stalagmites deposition rate, dripping water sites, etc. caused the initial ²¹⁰ Pb specific radioactivity difference among the three caves.