They were both taken to the Emergency Department at Gisborne Hospital for treatment.
The accident closed both lanes of the state highway.
"When we got there the truck and trailer were right across the road from one side to the other, and the trailer was still attached to the truck," said Matawai fire chief Neville Tohill.
The unit was carrying a load of squash for stock feed.
"The squash was all over the road and the smell was terrible," Mr Tohill said.
Firemen were at the scene of the crash for about four hours.
Roading contractors Fulton Hogan were in charge of the road cleanup.
A crane from C.R.Taylor Ltd was used to recover the truck and its trailer, which were to be put on transporters and brought to Gisborne.
The highway was reopened to one-way traffic about 9.15am.
