AUSTRALIA'S top spy agency is targeting Facebook users in a new recruitment campaign.

Some Facebook users with links to Sydney, Melbourne or Canberra have been seeing ASIO job advertisements in the past two weeks.

ASIO's quietly launched online recruiting drive is part of a broader campaign the agency said was aimed at "both passive and active job-seekers".

"We are seeking candidates from a broad range of backgrounds and social-networking sites provide access to a wide audience who may not otherwise consider ASIO as an employer," an ASIO spokeswoman said.

"We have used demographic filters on the site, simply because these roles are based in Sydney, Melbourne and Canberra."

The Facebook ad shows an ASIO logo accompanied by the caption: "What would it take for you to click on this ad? A snap decision? An inquisitive mind? Click for info on becoming a Surveillance Officer."

ASIO said the ads started appearing on February 12 and will run until March 5.