The crash came only hours after a woman was seriously injured in a three-car collision near Milford Sound.
Police said a Toyota Prado with five occupants crossed the centre line on a moderate bend about 10km from Milford as it was driving towards Te Anau.
The car collided with a sedan travelling towards Milford, injuring its two occupants, who were both 24-year-old women.
One suffered minor injuries while the other was flown to Southland Hospital with serious injuries.
The Toyota then hit another vehicle, but none of its six occupants were injured.
The Toyota's driver, a 49-year-old man, would be charged with careless use of a motor vehicle causing injury, police said.
Rain, speed and inattention were all believed to be causes in the crash, police said.