The man was skiing on Sunday afternoon with a 61-year-old companion, also from Germany, on the southern slopes of the Piz Nair at the Corviglia ski area when an avalanche swept the pair down the hillside, cantonal police said.
The incident occurred shortly after 2pm, when the snow slide triggered 50 metres below the 3,057-metre Piz Nair summit, which overlooks the resort town of Saint Moritz, police said in a news release.
The older man was partly buried in the snow while the younger man was completely buried, according to the release.
A third man who was skiing in the area and who saw the accident was able to pull the 61-year-old out of the snow.
A 20-member rescue team equipped with probing rods and aided by two dog teams took about an hour to recover his totally buried colleague, police said.
He was transported by helicopter to the Chur hospital for treatment of serious injuries from which he did not survive.
Police said both men were not carrying avalanche safety beacons.
Piz Nair is readily accessible from Saint Moritz via a funicular and a cable car that unloads 30 metres below the summit.