The crash happened around 7 pm at the intersection of 41 Southbound and East Nebraska Avenue.
The California Highway Patrol says a Silverado pickup truck was crossing the intersection with the highway but did not stop.
They say it crashed into a Dodge pickup truck that was hauling a fifth-wheel travel trailer.
The man driving the Silverado who did not stop has been identified as 57-year-old Mark Bruce of Fresno. He was killed in the crash.
Two of the three female passengers in his truck were also killed. They have been identified as 18-year-old Blanca Villegas Martinez of Selma and 17-year-old Dezirae Perez of Fresno.
3 dead, 4 injured after car crash on Highway 41 near Caruthers, CHP says
The CHP says they were not wearing seatbelts, and all three of them were ejected.
The fourth person in the truck was flown by helicopter to CRMC with major injuries.
As for the Dodge truck that was hauling the camper, there were three people inside.
Two men, one in their 30s and one in their 40s, and a 4-year-old who was in a car seat.
CHP says they all survived the initial crash and were taken to local hospitals.
Investigators say they are still working to determine if drugs or alcohol played a role in the crash.
The investigation remains ongoing.