New figures show delays in at least two Scottish health boards meant that adults had to wait 105 weeks before starting psychological treatment.
The statistics, issued to the Scottish Conservatives under Freedom of Information laws, show the maximum wait in the NHS Lothian region was 105 weeks in the April to June annual quarter last year.
Miles Briggs, Conservative Lothian MSP and party mental health spokesman, spoke of his shock at the figures, claiming it showed mental health issues were not being given serious enough attention.
He said: “It’s incredible to think anyone would have to wait more than two years to begin treatment for something of such importance.
“These aren’t isolated cases – at least two health boards had patients waiting that long, while many others weren’t far behind.
“That is not the mark of a Scottish Government that is taking mental health seriously enough.”
The figures show at least one patient in the Grampian area also had to wait 105 weeks before beginning psychological therapy some time between January and March 2016.
Elsewhere, there were waits of 104 weeks in Ayrshire and Arran in 2015, 93 weeks in Fife currently, and 64 weeks in Glasgow last year.
The Scottish Government target is for people to begin psychological therapy within 18 weeks of being referred.
Dr David Farquharson, medical director at NHS Lothian, said: “I would like to apologise to anyone who has had to wait longer than they should have for an appointment, particularly for psychological therapies. Our staff are working hard and are committed to increasing capacity and minimising waiting times for our patients.
“We continue to invest in our mental health services to ensure patients are seen as quickly as possible, with plans to invest approximately £1 million in the coming year to build capacity.
“We have recently recruited additional psychological therapists.”