Stores including LJ Hooker, Ambience Hairdressing, and the Gadget Doctor were destroyed, while fire crews were narrowly able to save The Good Guys and The Base Warehouse at the back of the complex.
Crews were called to the complex on Karalta Road, Erina, early on Thursday morning.
They arrived to find three shops alight with flames burning through the roof, NSW Fire and Rescue (NSWFR) said.
Nine crews and about 40 firefighters are on scene and the fire is now under control.
NSWFR says five shops have been badly burnt.