A fire which caused more than $300,000 damage to four businesses in Henley Beach South is thought to have been started by a malfunctioning kitchen appliance.

Just before 6pm witnesses noticed smoke pouring from the roof of the Yankee Cafe on Henley Beach Rd.

Everyone was evacuated safely.

More than 30 firefighters from eight units fought the fire, restricting the flames to the cafe.

It took an hour for firefighters to gain control of the fire and fully extinguish it.

The fire was restricted to the cafe but a baker, butcher and barbershop in the same building block were smoke damaged.

The MFS believe the fire begun in the kitchen from a faulty appliance.

The fire caused an estimated $300,000 damage.