The passenger was pronounced dead at the scene following the incident at about 03:30 BST on Monday.
It happened on Bryn Terrace, Aberdare, and the 25-year-old driver of the red LDV Maxus van, from Aberdare, has been arrested on suspicion of causing death by dangerous driving.
Those injured were taken to hospitals in Llantrisant and Merthyr Tydfil.
South Wales Police wants witnesses or anyone who saw how the van was being driven just before the crash to contact them on 101.
A woman has died and seven others have been injured in a van crash in Rhondda Cynon Taff.