The accident happened in the Preinerwand area. The climbers, aged 27 and 36, were roped together and were using hooks secured to the mountain face but were “not technically secured”, police said.
At around 2:00pm on Tuesday one of the men lost his footing and fell a distance of 50 metres, pulling his companion down with him.
"Witnesses who saw it happen immediately called the Alpine emergency team who sent out two rescue helicopters and alerted the police,” Philipp Gutlederer from Lower Austria's emergency control centre said.
Rescue teams arrived quickly and winched the men to a place where they could receive first aid but their injuries were so serious that they died before they could be taken to hospital.
Alpine police are now investigating what caused the fall.
Gutlederer said the rescue operation took several hours as the accident happened 1,800 metres above sea level and the men's location was hard to get to. People who saw the accident were cared for by a Red Cross team.