In a brief statement, it said that the plane had taken off from the Kuantan air force base at 11am and lost contact half an hour later at 11.30am Thursday.
The RMAF said that a search and rescue operation is currently underway.
The Hawk 108 is an export version of the Hawk 100, a two-seat advanced weapons trainer with additional avionics, optional forward-looking infrared, a redesigned wing and hands-on throttle-and-stick.
The aircraft is fitted with a BAE Sky Guardian Radar warning receiver and wingtip air-to-air missile rails.
The Hawk 108 is a predecessor to the Hawk 208 fighter jet, which was used in air strike missions in Lahad Datu during Ops Daulat in 2013.