Abstract: Interglacial climate is one of the major concerns in paleoclimate investigations. The stable oxygen isotope of a stalagmite (SJ5-6) from the Songjia Cave in northeastern Sichuan, central China, which is precisely dated with ²³⁰Th dating method, show prominent paleoenvironmental changes during the MIS (marine oxygen isotope stage) 9. The stalagmite of SJ5-6 developed from 334 ka to 320 ka, a part of MIS9. The variations in δ¹⁸O of the stalagmite are interpreted as the responses to the millennial-scale fluctuations of the Asian summer monsoon intensity during 334~320 ka. The δ¹⁸O record studied is roughly parallel with the other speleothem δ¹⁸O records recovered from the Asian summer monsoon region. In particular, there is a high similarity of temperature pattern between the stalagmite SJ5-6 and the Antarctic ice core. This suggests that temperature changes over the Antarctica may play an important role in the evolution of the Asian summer monsoon during the past interglacial.