The Yuba County Five refers to a group of young men from Yuba County, California, who each had mild intellectual disabilities or psychiatric conditions. They were reported missing following their attendance at a college basketball game at California State University, Chico, on the evening of February 24, 1978. Four members of the group Bill Sterling, aged 29; Jack Huett, aged 24; Ted Weiher, aged 32; and Jack Madruga, aged 30 were subsequently discovered deceased, while the fifth member, Gary Mathias, aged 25, remains unaccounted for.

Days after their disappearance, the group’s vehicle, a 1969 Mercury Montego registered to Madruga, was located abandoned in a secluded area of Plumas National Forest, situated on a high mountain dirt road that was significantly off their intended route back to Yuba County. Investigators were unable to ascertain the reasons for the vehicle's abandonment, as it was in good working condition and could have been easily extricated from the snow in which it was lodged. At that time, no evidence regarding the whereabouts of the men was uncovered.

Following the melting of snow in June 1978, the remains of four men were uncovered.