3fivetwo said most of the money will be spent on building a cardiac assessment and imaging centre as part of the Kingsbridge Private Hospital on Belfast's Lisburn Road.
CT and MRI scans will be available as well as cardiac investigations.
The group said it will also be spending £350,000 on a training centre on the Boucher Road in south Belfast.
"As waiting lists have grown, so has demand for our services," Mark Regan, 3fivetwo's business development director said.
"With government budget cuts set to bite even deeper, we expect demand to increase exponentially into 2016 and beyond."
A private health care company is creating 20 jobs and investing another £3m in an expansion programme.