The Olympic champion headed into the World Cup finale knowing that only German team-mate Johannes Rydzek could spoil his party.
But while Rydzek could only finish ninth in 29.17.3 minutes, Frenzel wrapped up a tenth win of the season as he won in 28:49.7.
That meant that Frenzel finished the campaign on 1734 points, with Rydzek second with 1609 and Akito Watabe of Japan third with 1086 after he finished third in Schonach.
Completing the podium in Schonach was Francous Braud of France who was 7.7 seconds behind Frenzel.
Read the original article on Eurosport: Fifth-straight World Cup title for Frenzel