Seiichi Eto, minister in charge of Okinawa and Northern Territories affairs, visited the war-linked Yasukuni Shrine on Thursday, becoming the first Cabinet minister to do so in over two years.
His visit, on the first day of the shrine's autumn festival, is certain to anger China and South Korea, which suffered from Japan's wartime aggression.
Prime Minister Shinzo Abe sent a ritual offering earlier in the day to the Shinto shrine, without making a visit in person. Abe last visited the shrine, viewed by Japan's Asian neighbors as a symbol of Tokyo's past militarism, in 2013.