Taxpayer-funded laptops and mobile phones valued at $484,000 were either stolen or lost from West Australian Government departments in the last financial year.

State Opposition Leader Mark McGowan said that was an increase of $40,000 on losses from the previous year.

He said more than 700 of the devices had been reported missing, including 280 laptops and 29 mobile phones valued at $242,900 from the Department of Education alone.

WA Police and the Health Department had losses valued at $61,212 and $34,581 respectively.

Mr McGowan said the Government had failed to address the issue, despite promising to do so at the end of the previous financial year.

"Loss of taxpayers' money of course is concerning, but on top of that there's the loss of data, and some of it could be secret data from the police, so it is concerning and it's also concerning that the Government said it would crack down on it happening in the future, and yet it's getting worse," he said.

Premier Colin Barnett said he was disappointed that agencies had not addressed the issue.

In a statement, Mr Barnett said the losses represented a small proportion of the devices issued to departments but were still of significant concern.

He said he would seek the assistance of the Auditor-General on how to better address the issue.