As of October last year, the longest wait for access to services before was three years and one month in NHS Highland, according to new data revealed under Freedom of Information request by the Liberal Democrats.
The longest wait time in NHS Fife was two years and three months as of December.
The largest number of patients waiting 12 months or more for an appointment was 431, in NHS Highland.
As of September 30 last year, there were 26 patients in NHS Lothian who had been waiting two years or more.
Liberal Democrat leader Willie Rennie said the the figures showed the “tragic” state of child and adolescent mental health services before the pandemic.
"At a critical moment in their life, children are waiting years for help,” he said.
"Staff are working around the clock but they've never had the support, resources or early interventions.”
The Scottish Government has set the target of at least 90 per cent of patients waiting no more than 18 weeks for CAMHS care, but Mr Rennie said the government had “not come close” to meeting these targets.
Ahead of the Holyrood election, he said: “If there is a nationalist majority, nothing will change. They badly neglected services, haven't come close to meeting the treatment targets for seven years, and even fought against Scottish Liberal Democrats leading Parliament in declaring a mental health crisis.
“An extra £120 million has just been injected into mental health because the Scottish Liberal Democrats secured it through our budget negotiations.”
SNP mental health minister Clare Haughey said: “Mental health is one of the most important public health issues facing Scotland today and that is why, even before Covid, the SNP had made it a priority, with a particular focus on investment in and redesign of child and adolescent mental health services.
“We are committed to building upon the work we have already set out to tackle mental health, and our mental health strategy is helping to reshape how CAMHS is delivered – underpinned by the principle of ‘ask once, get help fast’.”