The supercars tried to overtake each other before colliding and swerving into the van - which flipped over - in Sardinia on Monday.
A pair of Swiss tourists in the Ferrari were killed after the car burst into flames.
Melissa Krautli, 63, and Markus Krautli, 67, were named as the victims.
A couple from Selva di Val Gardena, aged 61 and 62, were taken to hospital with non-life threatening injuries alongside the pair in the Lamborghini.
Footage posted online shows a blue Lamborghini attempting to overtake a big white camper van by going in the opposite lane.
A red Ferrari then speeds alongside the Lamborghini but the cars collide, sending them hurtling towards the van which topples over.
According to local media, the Ferrari later burst into flames, trapping the couple inside as they burnt to death.
The remains of the three vehicles have been taken in by local authorities as they continue to investigate the incident.
The horror crash took place during the Sardinia Supercar Tour, in which luxury cars drive from Teulada to Olbia.