NHS Tayside and Fife made more than £4 million worth of overtime payments to nurses in 2016.
A Freedom of Information request submitted by the Scottish Conservatives found that more than £26.5 million was paid out across Scotland in 2016/17.
While this was £571,000 lower than the previous year, it was still over £4.8m higher than in 2014/15.
NHS Fife paid £1,314,334 in 2016/17, while NHS Tayside paid £2,826,358.
Conservative MSP Murdo Fraser MSP said: “The fact that so much money is being paid in overtime payments indicates that the SNP has got its workforce strategy all wrong.
“Fortunately, we have a group of nurses who are dedicated and willing to work significant overtime in order to deliver care but it shouldn’t be this way.
“Resources are being stretched thin and I’m sure many nurses in Tayside in Fife would prefer to have additional support rather than overtime cheques.
“Nurses vacancies reached a record high last year and the Scottish Government must work harder to ensure more are trained and retained.
“Healthcare services are being stretched thin and its high time that the SNP got overtime payments under control in Tayside and Fife and gave our hardworking nurses a break.”
A spokeswoman for NHS Tayside said: “Our highest priority is always to ensure that our patients receive high quality care.
“We offer overtime to nursing staff in response to unexpected and unpredicted gaps in service, such as short notice sickness absence and only when we have been unable to secure bank nursing staff.
“Like many other health boards, NHS Tayside can sometimes face hard-to-fill vacancies in some specialities.
“We actively recruit to all nursing vacancies and we have opened up the opportunity for all registered nurses, midwives and healthcare support workers to join the NHS Tayside Nurse Bank to increase capacity and reduce our use of supplementary staff.
“We also have a proactive recruitment strategy of new graduates from universities and were successful last year in recruiting 167 newly qualified nursing practitioners.”