Health secretary Nicola Sturgeon said more could be done to address the issue, despite statistics showing an improvement.
The latest figures showed the compliance rate for hand hygiene in hospitals had increased to 94 per cent among all workers. But the rate varied amongst staff groups, with doctors the worst offenders.
The latest hand hygiene audit showed the compliance rate for doctors was at 86 per cent, lower than the target of 90 per cent.
Liberal Democrat health spokesman Ross Finnie said: "I am concerned that doctors are still lagging behind when it comes to washing their hands. There is simply no excuse for this, particularly given the high-profile hygiene drive after the swine flu outbreak.
"Infections in hospitals cost lives. As senior medical professionals, doctors should be setting an example for other health workers to follow."
Allied health professionals, such as physiotherapists, radiographers and podiatrists, had the best compliance rate of 96 per cent. Nursing staff were at 95 per cent and among other ancillary staff, such as porters and cleaners, compliance was at 94 per cent.