Loch had the fastest time in three of the four runs and finished his last one with an aggregate time of 3:27.526.
The luge has been contested 14 times at the Olympics and this was the ninth victory for a Germany. Loch is just 24 years old and in a sport where experience is the key ingredient he could be around long enough to challenge the numbers piled up by German Georg Hackl.
Hackl won three gold medals and two silver ones over the course of five Olympics beginning at the 1988 Games in Calgary.
The silver medal was won Sunday by Albert Demchenko of Russia, who also finished second eight years ago in Turin. Armin Zoeggeler of Italy wound up third, giving him a medal in this event for the sixth straight Olympics.
Zoeggeler won a bronze in 1994, a silver in 1998, a gold in both 2002 and 2006 and a bronze in 2010.
Demchenko had the best time in the first run of the competition, turning in a 52.170 while Loch was clocked in 52.185.
Loch edged Demenchko over the next three runs by .309, .094 and .088 of a second.