The Men's K1 at the 2021 ICF Canoe Slalom World Championships took place on 23 and 25 September 2021 at the Čunovo Water Sports Centre in Bratislava. It was the 41st edition of the event, and 80 athletes from 36 nations competed. The event was won by Boris Neveu of France, winning his second title, after he led a French one-two-three in 2014. Italian underdog Marcello Beda won silver in his first international final, while Joan Crespo matched his result from 2019 with bronze.