The crash at about 6:30 p.m. EDT (2230 GMT) on Friday was between a Dodge pickup traveling west and a group of motorcycles traveling east on a state highway in Randolph, just above the White Mountains about 120 miles (193 km) north of Manchester, state police said.
One of the injured was airlifted to a hospital and the highway was closed for much of the night during the clean-up and investigation, police said in a statement.
New Hampshire Governor Chris Sununu said he and his wife Valerie were "deeply saddened" to learn of the crash.
"Our thoughts and prayers are with the victims, their families, & first responders who answered the call," he wrote on Twitter.