Ambulances went to the scene on the A12 just before 1600 GMT on Saturday.
Of the seven injured, two were taken to the Royal London Hospital and five to Queen's Hospital in Romford. The extent of their injuries are not yet known.
One man has been arrested on suspicion of causing death by dangerous driving and remains in custody at an east London police station.
Two people travelling with the deceased man were taken to hospital, where they are in a stable condition.