All three walked away just days after starting the £12,000-a-year job, blaming intimidation from smokers.
The wardens were hired as part of an NHS drive to stop people flouting no smoking rules outside hospitals.
It was hoped they would encourage people to stop lighting up as doctors have warned the fog of smoke at hospital
doors could harm the health of visitors and patients.
The three wardens began work last week at Gartnavel Hospital in Glasgow, which is also home to the Beatson West of Scotland Cancer Centre.
But they quit within days, citing unbearable intimidation and verbal abuse from people they caught smoking in the grounds. NHS Glasgow and Clyde rolled out the scheme at 11 hospitals, employing 17 full-time wardens.
The scheme has seen them rebrand hospital entrances with red warning signs and giant no smoking zones.
The board's director of public health, Dr Linda de Caestecker, said: "Despite early signs of success I am extremely disappointed at the level of verbal abuse that has been spouted at some of our smoking wardens.
The moves to enforce the smoking ban outside hospitals came after the Sunday Mail published shockingpictures of smokers ignoring warning signs.
Comment: Shocking pictures!? How shocking!
As they say in Bonnie Scotland, 'git tae fock'!
Gordon Stewart, a smoking warden at the Southern General in Glasgow, said: "Around one in 10 smokers we approach are abusive. The rest either put out their fags or move outside the grounds.
"We have even had patients in wheelchairs and on drips smoking.
"One woman patient told me to f*** off then called me a c***.
"She said she would smoke as many cigarettes as she liked just to p*** me off but she did apologise later."
Colleague James Willison, 21, added: "The abuse is not nice. We are only trying to help. We also hand out advice to smokers on how to stop. But a small minority just do not want to know."
Comment: Yeh well, you're not helping. At all. People are stressed beyond belief, and you are making them more stressed, so stop it! You don't have a clue what you're talking about, so you have no good advice to give. Cease! Desist!
Fiona Dunlop, who is responsible for the anti-smoking campaign, added; "Smoking on hospital grounds is one of the most complained about issues by staff, visitors and patients.
"Smoke from cigarettes can get into the hospital and harm patients.
"And staff who are caught smoking could face disciplinary action."
In the first week of the campaign, 32 patients and 25 visitors refused to stub out their cigarettes.