Four police cars and three fire crews, from Greerton, Tauranga and Matamata attended the crash, near the intersection of Soldiers Rd and State Highway 29, at 2.10pm yesterday.
Greerton Fire Service station officer Richard Moreland said the man was removed by the back door of the car, which had come to rest about 4m down the bank. At the bottom of the steep, scrub-clad gully was a river.
He was carried up the bank in a stretcher and stabilised at the scene.
Police last week began a five-month campaign targeting poor or dangerous driving in the region's worst black spots. State Highway 29 was one of those to be targeted.
The social cost of fatal crashes on the Kaimai ranges over the past five winters reached $18.34 million. The cost of serious crashes there reached $8.12m.