Former Imperial Japanese military personnel suffered from PTSD much like soldiers in other parts of the world. Hiroshi Shimizu, a professor emeritus at Saitama University, analyzed the medical records of 8,000 former soldiers, and found that about 29,200 Japanese Army soldiers were admitted and discharged from hospitals immediately after the war, and half of them, about 14,500, suffered from various mental illnesses. Shimizu identified six types of these mental illnesses:

• Fear of combat (caused by fear and anxiety during combat activities)
• Combat exhaustion (due to fatigue from marching and other combat activities)
• Military maladjustment (due to maladjustment to military life)
• Private sanctions (due to private sanctions in military life)
• Remorse (due to remorse for military actions)
• Guilt by assault (due to feelings of guilt for the assault)

Source: https://www.buzzfeed.com/jp/kotahatachi/ptsd-ww2

PTSD is linked to postwar suicide, domestic violence, and homicide. There is a support group called PTSDの復員日本兵と暮らした家族が語り合う会 (Discussion group for families living with demobilized Japanese soldiers suffering from PTSD) (website: https://www.ptsd-nihonhei.com/ ) which was started by Kuroi Akio, a son of a veteran who served for 7 years fighting in China in the Imperial Army and was held as a prisoner of war for one year by Chinese forces before returning to Japan at age 34. His father never held a stable job due to apathy and anxiety issues which, in retrospect, were linked to his military service, and his family lived in poverty throughout his childhood. Kuroi said that there were many members of his group who suffered from physical and verbal violence by their fathers (see https://www.nishinippon.co.jp/item/n/652247/ ). One member reported frequent violence, including a veteran who threw hot miso soup at his wife (see https://www.ptsd-nihonhei.com/ptsd%E5%85%B5%E5%A3%AB-%E5%AE%B6%E6%97%8F%E3%81%AE%E5%A3%B0/ ).

Edit: Fixed formatting.