Charly Grosskost (5 March 1944 – 19 June 2004) was a French racing cyclist who, in 1968, won the prologue time trial of both the Giro d'Italia and the Tour de France.

He won stages of the Tour de France and the Giro d'Italia, and on the track, he was French pursuit champion nine times.

A drug test that followed his retirement – it has entered cycling legend that other riders pushed him off his bike for his own safety as he began foaming at the mouth and riding erratically – led to his being suspended for a year.

Grosskost turned professional for Peugeot on 1 May 1966, alongside Eddy Merckx of Belgium, whom he beat to win his Giro prologue.

In 1968 he won the prologue of the Giro d'Italia and became the third Frenchman to wear the leader's pink jersey after Louison Bobet and Raphaël Géminiani.