Akita-Komagatake volcano continued eruptive activity within the southern caldera at the summit from 3 ka until about the 10th century, erupting low-potassium series basalt to basaltic andesite magma. The volcano had been dormant since then for about 1,000 years but erupted in the 20th century in 1932 CE and 1970 CE. The 1970 eruption ejected the andesitic magma that is different from those of previous ones, suggesting that the magma system may have changed in the 20th century. To clarify the timing, we re-examined the 1932 ejecta around the craters, which was previously thought to be products of phreatic eruption. The deposit is tuff breccia with scoria and accessory lithics, both of which are coated by thick, silty ash. Large ballistic blocks are also scattered throughout the area. The scoria shows an unrounded, fragmented shape and is a porphyritic clinopyroxene-olivine basaltic andesite. Considering the unaltered petrographical characteristics and the fragmented shape, the scoria can be considered as a juvenile material of the eruption. Thus, it is concluded that the 1932 eruption was phreatomagmatic. Although the chemical compositions of the scoria (SiO₂＝ca. 53.0 %) is plotted on the trend in SiO₂ variation diagrams formed by juvenile materials during the last 3,000 years, those of the 1970 lavas (SiO₂＝ca. 58.5 %) are not plotted on the trend. This suggests that the magma system of the volcano changed after the 1932 eruption.