Pieter "Peter" van Doorn (born 29 January 1946) is a retired Dutch cyclist who was active between 1969 and 1975. Between 1969 and 1972 he won four consecutive national titles in the tandem. He competed at the 1972 Summer Olympics in the sprint, 1 km time trial and 2 km tandem events and finished in fifth, eleventh and fifth place, respectively.