The incident happened at about 3.15pm yesterday on the B1253 close to Sledmere, which lies north west of Driffield.
Humberside Police said the victim was thought to be a man in his 50s from the Driffield area, although formal identification has yet to take place.
He was riding a green Specialized Allez bike when it was in collision with a white Iveco tipper.
The driver of the lorry, a 29-year-old Bridlington man, was treated by paramedics for shock.
Police are appealing for witnesses to the incident to contact them on the Humberside force’s 101 number, quoting log reference 322 of November 25.