Ten stalagmite samples from Guangxi and Fujian of south China have been studied and their paramagnetic defects and the complex ESR signals have been researched. For each ESR signal

the response to radiation dose was different. The responses of two signals (g=2.0007 and g=2.0023) were found more sensitive. The mean life of signal g=2.0023 was only 4.8 years at 20℃

but that of the signal g=2.0007 was about 105 years

therefore the signal g=2.0007 can be chosen for ESR dating. The effect of sa-mple’s grinding on the dating was also discussed.