A MAN allegedly found asleep at the wheel while still holding a can of bourbon at an Adelaide petrol station has been busted for drink driving.

A police patrol spotted the man when they arrived at the BP On The Run on West Tce, in Adelaide's central business district, about 9.30pm last night.

The man was asleep in the driver's seat of a green Holden sedan and still holding a can of bourbon, police said.

A check of CCTV vision showed the man driving into the service station and stopping at the petrol pump.

When woken, he was breath tested and returned a reading of 0.239, almost five times the legal limit.

He was reported for driving under the influence, exceeding the prescribed concentration of alcohol, driving unregistered and breaching his provisional licence conditions, which require a zero blood alcohol level.

The man lost his licence for for year, had his car impounded for 28 days and will appear in court at a later date.