It happened around noon at the intersection of Highway 141 and County Highway P in the Town of Beaver.
Police say a car driven by a 19-year-old male from Coleman, Derek Marquardt, was eastbound on County Highway P attempting to cross Highway 141 from a stop sign.
The car collided with a southbound motorcycle, with both the 52-year-old operator, Jerry Groeschel, and his 54-year-old wife, Debra Groeschel, sustaining serious injuries. The Kimberly couple was transported to a local hospital.
Police say the driver of the car and his 16-year-old passenger also sustained minor injuries.
Authorities say Debra Groeschel's injuries were life-threatening. She was later flown by Eagle III to a Green Bay Hospital.
The crash remains under investigation. Alcochol and drugs are not considered factors in the crash.