The accident happened when work was being carried out to shorten a cable in the lead-up to the busy summer season.
However, during the work, which was scheduled to take four days, cable supports gave way and a cable struck workers.
A local resident told Swiss tabloid Blick that there had been a sound like a “crack” when the cable came free.
One worker – a long-time worker with the Titlis cable car operator – suffered severe injuries and died on the scene. Three other workers were taken to hospital – two of them with serious injuries.
A further three workers suffered only minor injuries and were treated on the scene.
No cable cars were operating at the time of the accident and no tourists were injured.
Hans Wicki, the chairman of the board for Titlis Cable Cars said on Wednesday that it was “the worst day in the company’s history”.
Wicki said he had spoken to the family of the man killed.
“His relatives told us that their father loved his job but he always knew it was risky,” he said.
Possible material defect
Investigators are now looking into the cause of the accident.
The director of cable car manufacturer Garaventa described the work of shortening cables as “routine”.
But the CEO of Titlis Cable Cars, Norbert Patt, said investigations into the possible cause of Wednesday's accident were likely to take some time.
A forensics team will examine whether these were any issues with the materials being used.
Popular tourist destination
The cable car affected is the Titlis-Express which runs from Engelberg to the Trübsee cable car station.
Brought into operation in 2015, this cable car can transport up to 2,400 tourists an hour.
The very popular Titlis network of cable cars transports around 1.2 million tourists a year.