Kelowna RCMP Const. Kris Clark said the collision happened shortly before 5 p.m. PT approximately nine kilometres west of Osoyoos, near Spotted Lake.
Clark said it appears one semi-truck with trailer was passing another, and may have sideswiped it in the process.
Both vehicles were engulfed in flames after the impact. One driver got out and away without injury, but the other driver had to be rescued and was airlifted to hospital with non-life threatening injuries.
Flames from the crash started a ground fire, which spread quickly in the dry grass on the highway's shoulder.
Forestry officials arrived on scene and began conducting aerial operations in an effort to contain the blaze and stop it from spreading to a nearby house, Clark said.
The highway was closed in both directions for several hours, and Drive B.C. announced just after 8:30 p.m. PT that the highway had reopened to single-lane alternating traffic.