In an online survey of its members by the Royal College of Nursing (RCN) Scotland, 60 per cent of 1,916 respondents agreed the pressure on them is too high.
Six in 10 (60 per cent) said they feel too busy to provide the level of care they would like to, and 70 per cent said they work over their contracted hours at least once a week.
Around half of the respondents (53 per cent) who said they work over their contracted hours also said those additional hours were unpaid.
As many as 83 per cent of those who responded to the survey said they had gone to work at least once in the last 12 months despite feeling too ill to do so.
• READ MORE: Thatcher made NHS a factory, SNP should restore health service of old – Harry BurnsThe survey also found 62 per cent feel their pay is either inappropriate or very inappropriate, with 35 per cent thinking about looking for a new job.
A total of 69 per cent of respondents said they had experienced verbal abuse by patients/service users or relatives, while 31 per cent had experienced physical abuse.
Additionally, 37 per cent said they had experienced bullying - an increase on the 32 per cent who said they had endured it in 2017.
Theresa Fyffe RCN Scotland director, said: "At its best, nursing gives people a sense of identity, pride, achievement and huge fulfilment.
"But it's clear that nurses and healthcare support workers are feeling overworked in under-resourced environments.
• READ MORE: Our dedicated NHS staff deserve so much better – Alison Johnstone"It's time to make staff wellbeing a major priority and the first step is to safeguard staff psychological health through the guidance and implementation for the safe staffing act."
Scottish Conservative health spokesman Miles Briggs said the SNP should take full responsibility for the "disgraceful state" of the health service.
He said: "The SNP has driven Scotland's NHS into a desperate state.
"Its workforce planning has been so shambolic that we're seeing record levels of vacancies and wards across the country struggling for workers.
"That all means those nurses who remain have to pick up the slack, and it's now taking its toll.
"The nationalists have been in sole charge of the NHS for more than 12 years, and have to take full responsibility for this disgraceful state of affairs.
"The decision by Nicola Sturgeon to cut the number of trainee nurse and midwife places in Scotland while she was health secretary has created a major shortage in nurses across Scotland.
"And all this simply piles more pressure on (current Health Secretary) Jeane Freeman, who's failed to make an impact on any of these issues."
Health Secretary Jeane Freeman said: "We value the dedication of our hard-working nurses and we take their welfare very seriously.
"The number of nurses in Scotland is 45% higher per head than it is in NHS England with qualified nurses and midwives in Scotland having increased by 2020.
"Earlier this year, we passed our new safe staffing legislation which will help ensure that our health boards have the right number of staff in the right place. It is the only comprehensive safe staffing law anywhere in the UK.
"For nurse training, we protected free nursing tuition and have not only kept their bursary, but we are increasing it to £10,000 from next year while the UK Government have scrapped free tuition and bursaries for nursing students in England.
"Our integrated workforce plan will be published in the near future, and will build on the three workforce plans for the NHS, primary care and social care that have already been published."