The crash occurred around 1:10 p.m. Friday near the Concordia College campus.
Seward police say it appears 80-year-old Richard Roth was driving when he had a medical problem before his pickup struck the tree.
Police say he and his 80-year-old wife, Eleanor, were taken to Seward Memorial Hospital. He was pronounced dead there. She died after being transferred to a Lincoln hospital.
The couple lived in Seward.