A man has been rushed to hospital after he was reportedly injured in a fire at a Perth auto-shop on Monday morning.

The fire started just after midday near Precision Automatic Transmissions on Ruse Street in Osborne Park.

The area was evacuated due to concerns regarding around 20,000 litres of motor oil and other dangerous chemicals inside the shop.

St John attended the scene, and treated two men for unknown injuries.

One man was taken to Fiona Stanley Hospital on priority, after it was found he had been seriously burned by the fire from the waist up.