A man is in a serious condition burns to 50 per cent of his body after an explosion in an underground carpark in Sydney's inner-west.

Emergency services were called to the Ashfield Mall shopping centre on Liverpool Road around 5pm on Friday afternoon, after reports a man had been severely injured in an explosion.

A man was severely injured in an explosion at Ashfield Mall.

A spokesperson from NSW Ambulance said it's believed the incident took place in a storeroom underneath the shopping centre, and may have involved aerosol cans.

The man was taken to Royal Prince Alfred Hospital in a critical condition with burns to his face, arms and legs.