The 22-year-old victim was a passenger in a blue Peugeot 206 that crashed into the wall at The Lounge club in Granada Road, Southsea.
The man, from Folkestone, Kent, who hasn't been named, was pronounced dead at the scene following the crash at a
bout 2.15am on Friday.
The car had just crossed the roundabout from Clarendon Road when it left the road and crashed into the club.
No-one is believed to have been inside the venue when the crash happened.
Police cordoned off Granada Road for about four hours while they investigated the scene.
The Peugeot driver, a 19-year-old woman from Gwent, Wales, was arrested on suspicion of causing death by dangerous driving.
She was treated for minor injuries at Queen Alexandra Hospital in Cosham.
Residents have told of their shock at the crash.
Ashley Robinson, 18, from Waverley Road, Southsea, said: 'I was asleep and I heard a massive crashing noise. It woke me up.
'At first I thought it was fireworks. I got up to see what it was and saw there was a blue car halfway across the pavement.
'The front was completely smashed up. It looked really serious.
'The police and the ambulance were here really quickly and shut off the road.'
Grim Hernandez, 21, from Granada Road, Southsea, added: 'The crash sounded like an explosion.
'It was really worrying. I got up and saw the neighbours all looking out of their windows.
'It's terrible.'
Anyone with information should call Sergeant Alyson West at the Eastleigh Road Death Investigation team quoting Operation Kitty on 101 or Crimestoppers anonymously on 0800 555 111.
