Its call sign was the Public Division (公兵団, Kimi Heidan).

As the Soviet invasion of Manchuria has started 9 August 1945, it fought a desperate defensive battle meeting Red Army forces south and west of Hunchun[2] while fighting the against Soviet "113th fortified sector" and 88th Rifle Corps.

The division's resistance was described as "heavy",[3] despite the estimate by the 1st Area Army that the 112th was only 35% combat effective.

Another Soviet attack supported by armour was beaten back 15 August 1945 at Unggidong.

Although the next Soviet attack was expected at Pungni-ju city, 16 August 1945 all of the division's units were engaged by Red Army forces simultaneously.