Abstract: The dynamic setting for future eruption of Tianchi volcano in Changbaishan Mountain is analyzed with the focal mechanism and tectonic geology. Study on the focal mechanism of anatectic earthquake shows that subduction of the West Pacific plate to Northeast China makes the near-west-east pressure in Tianchi region. The direction of the maximum principal compressive stress axis in the area is trending NEE. Research on structural geology reveals that NWW-trending faults around Tianchi are active since late Pleistocene. The future eruption of Tianchi volcano is possibly controlled by the subduction of West Pacific plate and the NWW-trending strike-slip faulting. On this basis, the dynamic setting for the future eruption of Tianchi volcano is put forward.