Phil Gaetjens is an Australian public servant and former Liberal Party staffer, who served as the Secretary of the Department of the Prime Minister and Cabinet from 2019 to 2022.

Gaetjens began his career in government in 1977 as an Assistant Research Officer in the Bureau of Transport Economics.

He joined the South Australian Department of Treasury and Finance as Assistant Under Treasurer for State Enterprises in 1995.

Gaetjens later became Director of the Asia-Pacific Economic Cooperation Policy Support Unit before returning to Australia in 2010.

On 25 November 2022, the Bell Inquiry concluded that it was troubling that Gaetjens did not take up the issue of the secrecy surrounding the appointments with Mr Morrison and firmly argue for their disclosure.