Kishida Fumio has been elected prime minister in the Diet. Lawmakers in both chambers voted for the newly elected leader of the Liberal Democratic Party, the main ruling party.
He was elected to lead the country in the Diet's Upper House soon after he was chosen as prime minister in the Lower House.
The 64-year-old political veteran succeeds Suga Yoshihide, who did not run for re-election as LDP leader.
Kishida is well known for his stint as Japan's top diplomat.
In his more than four years as foreign minister, Kishida worked to improve ties with Japan's neighbors and allies.
Notably, he organized the first visit to Hiroshima by a sitting US president.
Kishida is now forming his Cabinet. Later on Monday the Emperor will ceremonially endorse Kishida and his ministers at the Imperial Palace.
The new prime minister is then expected to hold a news conference and convene the first meeting of his Cabinet.