The findings, released ahead of next month's Scottish parliament elections, reveal the extent of the GP crisis facing Scotland.
More than half (58%) of the 150 respondents to the poll - carried out by ComRes on behalf of the RCGP - said they planned to quit or reduce their working hours in the next five years, while 9% plan to quit over the next 12 months.
A total of 77% of GPs said that they worried about missing something serious with a patient because of soaring pressure on workload, and 89% said that a lack of resources risked undermining patient care.
More than nine out of 10 GPs who took part in the survey said that without more resources, patients would be forced to wait longer for GP appointments, and a similar proportion felt morale had declined over the past five years.
RCGP Scotland chairman Dr Miles Mack said: 'GPs are already deeply concerned about the welfare of their patients as a result of a decade of cuts to the percentage share of funding the service receives, from 9.8% in 2005/6 to 7.4% in 2014/15, despite an 11% increase in the number of consultations over ten years. A wholesale departure of GPs now looks likely given the current conditions the profession faces. In that instance, patient safety clearly will suffer further.'
Political parties have set out plans to boost GP funding in the run-up to the Scottish parliamentary elections.
A manifesto released by the Scottish Conservatives pledged to increase the share of overall NHS funding spent on general practice, while the Scottish National Party government unveiled a £20m GP funding package in March.
Dr Mack said: 'General practice in Scotland is a defining issue in this Scottish parliamentary election. This is a service absolutely central to the NHS and to Scottish life. Patient safety is the concern of all political parties and of the entire electorate. I call on all the parties to make commitments which will guarantee the future of the GP service and increase funding to a sustainable level.'
In England, plans set out under the GP Forward View document published by NHS England this month pledge to lift the share of NHS funding spent on general pracice to more than 10% by 2020/21.