There were 225 members of Derbyshire teaching staff on long-term leave for mental health problems in 2016-17, figures show.
The statistics - obtained by the Liberal Democrats using the Freedom of Information Act - reveal a year-on-year rise of 12.5 per cent in the number of local teaching staff taking 30 days or more leave for conditions like stress and depression.
A senior Conservative politician at Tory-led Derbyshire County Council (DCC) insisted the authority is dedicated to supporting them.
Ross Shipman, Liberal Democrat spokesman for Bolsover, said Derbyshire's teaching staff face 'impossible pressures'.
He added: "It is simply unacceptable that those working tirelessly to do the best for local children are seeing their mental ill-health affected as a result.
"This must be wake-up call to the Conservatives on DCC.
"Stress and anxiety are fuelling the teacher recruitment and retention crisis - but the Government’s current approach is making matters worse.
"Derbyshire Conservatives need to pressure their colleagues in Government to end the real-term cuts to pay for teachers that are leaving them feeling overworked and undervalued."
Councillor Alex Dale, cabinet member for young people at DCC, responded: "I'm proud that the Conservative Government has put an additional £1.3billion into schools this year and has introduced a national funding formula to end the unfair postcode lottery that has existed until now. Our education and curriculum reforms over the past seven years and the hard work of teachers across the country has led to 1.9million more children being taught in good or outstanding schools. Having supported these reforms from 2010 to 2015, I'm disappointed that the Lib Dems now appear to be criticising our record on education.
"A closer inspection of the statistics reveals a different picture to the one presented by the Lib Dems. Another FOI response, limited to teachers rather than the broader category of 'teaching staff', showed a reduction in absence due to stress and mental health on the previous year and the number of calendar days lost due to stress was lower than it was four years prior.
"That said, I do acknowledge some of the pressures facing the teaching profession and want to pay tribute to the amazing work that Derbyshire's teachers do to provide our children with a good education in often challenging circumstances. Stress and emotional wellbeing issues are on the rise across many professions and it's important that the right support is made available.
"As a local authority, we offer a range of support to teachers, including the Derbyshire Counselling Service which is a confidential self-referral service for employees who may be experiencing problems at home or work. In addition, schools and academies can buy into our traded services such as occupational health, who offer work place assessments and in-service medicals. Alongside this they are also able to offer physiotherapy, cognitive behavioural therapy and assist with the provision of specialist equipment to help with reasonable adjustments in the workplace."