The climber is believed to have fallen about 100m (300ft) from Tower Ridge into a gully below as he ascended Ben Nevis, in Scotland on Saturday.
"At about 11:00 GMT a male climber fell from Tower Ridge into Tower Gully, Ben Nevis," a Northern Constabulary spokesman said.
"Lochaber Mountain Rescue were contacted and with the assistance of Royal Navy Search and Rescue the male was rescued from Tower Gully, however, he had sustained fatal injuries."
The man, who is English and in his 20s or early 30s, is believed to have been climbing alone, media reports said.
Tower Ridge is one of several ridges protruding north-west from the summit plateau of Ben Nevis, which stands at 1,344 metres (4,409ft) in the Scottish Highlands.
The fatality comes one week after four climbers lost their lives in an avalanche in Glencoe, also in the Highlands.