Sergio Villamayor (born 4 December 1989)[1] is an Argentine modern pentathlete.

[2][3] He won the bronze medal in the men's individual event at the 2019 Pan American Games held in Lima, Peru.

[4] He also won the bronze medal in the men's relay event, alongside Emmanuel Zapata.

In 2011, he competed in the men's individual event at the Pan American Games held in Guadalajara, Mexico without winning a medal.

Four years later, in 2015, he competed in the men's individual event at the Pan American Games held in Toronto, Canada, also without winning a medal.