Marinus "René" Augustinus Josephus Pijnen (born 3 September 1946) is a Dutch former racing cyclist.

He became Olympic champion in the 100 km team time-trial in the 1968 Summer Olympics with Joop Zoetemelk, Fedor den Hertog and Jan Krekels; he finished fifth in the individual road race.

[1] A professional from 1969 to 1987, Pijnen was a capable track cyclist, winning the European madison championship six times, a record he shares with Patrick Sercu).

[2] Pijnen rode on the road with TI–Raleigh, managed by another Dutch track specialist, Peter Post, but he said the length of road races bored him, and that he frequently found himself looking at his watch to see how much longer he would have to ride.

[2] When he retired, he ran – among other enterprises he already started during his cycling career – a hotel in Bergen op Zoom, the North Brabant province where he was born.