Abstract:Since the mid and late Holocene, Tianchi volcano, the Changbai Mountains, has mostly erupted pumice and formed pyrocalstic flows, with lavas rarely overfl owed. The lavapyroclastic flow Qixiangzhan Fm. was one of those lava overflows that have occurred very scarcely,and was erupted from an parasitic crater, consist of comendite, which has a large viscosity and is overf l owed slowly. According to our study, the Qixiangzhan lava erupted in the mid a nd late Holocene, i. e. about 4 ka BP, belonging to modern eruptions.