The Olympic champion improved on his first-run time of 43.510seconds with a record-breaking run of 43.447seconds to record an overall time of 1:26.957minutes.
The victory was Loch's fourth World Cup win of the season but there was also success for two of his compatriots who finished just behind him.
Andi Langenhan was second with a time of 1:27.152mins and Julian von Schleinitz, who was ranked 49th in the season standings heading into the event, was 0.566secs behind Loch in third.
Loch now leads the overall standings by 130 points, ahead of David Moller of Germany and Dominik Fischnaller of Italy, and requires just a second-place finish in Altenberg next weekend to seal the title.
� Sportsbeat 2014