The accident happened just before midnight Saturday night on Highway 99 near Avenue 264, between Tulare and Visalia.
An 18 year old driver lost control of his car. The car spun out, went off the road, and crashed into a tree.
The 18-year-old driver and two passengers -- a 19-year-old female and 22-year-old male -- that died in the accident. Three other passengers are in the hospital with major injuries.
The C.H.P. said they believe alcohol may have contributed to the crash.