Kishida won the race to lead the party on September 29, replacing Yoshihide Suga, who decided to step down after just one year in office, CGTN reported.
As the ruling coalition led by the LDP controls both chambers, 64-year-old Kishida secured a majority of votes of both the House of Representatives and the House of Councilors.
After naming his new cabinet in the afternoon, Kishida will be formally inaugurated in a ceremony at the Imperial Palace and hold a press conference in the evening.
Kishida's first major test as prime minister will be the general election. He is planning to hold the election on October 31, while campaigning for members of the House of Representatives is set to begin on October 19.