In this paper we describe the paleomagnetic measurements of the Aso-4 tephra in Yamaguchi Prefecture. The tephra is called the Ube Volcanic Ash Bed. Its lower and upper beds correspond to the Yame pumice-flow deposit and the Tosu orange pumice-flow deposit, respectively, in the region to the west of Aso caldera, central Kyusyu. We collected about 250 oriented samples at 9 sites in the lower bed and 11 sites in the upper bed. The stable components of remanent magnetization were isolated from the samples through stepwise alternating field demagnetization up to 70mT. The direction of the stable component was obtained using principal component analysis, anchored to the origin of Zijderveld diagram.<br>The paleomagnetic direction of the lower bed (Dm=1.7°W, Im=45.5°, α₉₅=2.6°) is consistent with those of the Aso-4A welded tuffs in Oita Prefecture, the Aso-4 non-welded pyroclastic flow deposits in Miyazaki Prefecture, and the Aso-4 co-ignimbrite ashes in the Chubu-Kanto-Tohoku district. On the other hand, the direction of the upper bed (Dm=0.9°W, Im=41.9°, α₉₅=3.4°) shows the intermediate direction between the Aso-4A and the Aso-4B in Oita Prefecture. The mean inclination of the upper bed is deeper than that of the lower bed by 3.5 degrees. This directional difference might be caused by geomagnetic secular variation.