Márcio May (born 22 May 1972) is a Brazilian road bicycle and track cyclist, who competed in three Summer Olympics (1992, 1996 and 2004) for his native country. He won two bronze medals during his career at the Pan American Games (1995 and 1999). May retired from professional cycling in January 2008. His last race was the Copa América de Ciclismo, in which he rode for the Scott–Marcondes Cesar–São José dos Campos team. He returned to racing at the amateur level in 2016, and currently rides for club team FMD Rio do Sul–Royal Ciclo–Dalthon.