The couple wed in an evening ceremony before family and friends in the Pacific Palisades area Saturday.
People said Deschanel, 33, wore diamond clips in her hair and diamond earrings, both by Neil Lane.
Deschanel is starring in the sixth season of Fox's "Bones"; Hornsby is best known for his work on FX's "It's Always Sunny in Philadelphia."
Police: Sword-wielding man demanded free tacos
N.J. man wakes up from 10-hour sleep with knife in back