Kennedy hit an eight under 63 at Millbrook today and came through in the back nine to win by two shots.
It is the second time Kennedy has won the Open, after winning in 2011.
Lucas Herbert, another Australian, needed a birdie on the last hole to tie with Kennedy but sent his tee shot into the water, killing his chances.
Michael Hendry and Harry Bateman were the best two New Zealanders, finishing six shots behind Kennedy who won the tournament with a 21 under par score.