It happened around 3:30 Saturday afternoon on the 100 block of Sunset Hill Road in Earl Township.
State Police say 73-year-old Harry Meyer was driving west when he lost control along a curve.
The vehicle struck two trees and landed on its left side.
Two passengers, 71-year-old Signe Wergeland and 51-year-old Sharon Richards, were killed in the crash.
Meyer suffered serious injuries and is listed in critical condition.
The roadway near the scene was closed for three hours but has since reopened.
Police are still investigating what sparked the crash.
