Ivan Calderon (born approx. 1981) is a boxer from Puerto Rico. Calderon attended the 2000 Olympics in Australia, but he lost there on the first tournament round. Calderon is a native of Guaynabo.
He also lost to Brian Viloria during his amateur boxing career.
After turning professional, Calderon has managed to raise the eyebrows of many Puerto Rican boxing fans, and he has been frequently showcased on ESPN's Friday Night Fights show.
On May 3, 2003, Calderon became a world champion for the first time, beating Eduardo Marquez by a technical decision in nine rounds at Las Vegas, as part of the De La Hoya-Campas undercard, to win the WBO's world Strawweight title. He had dropped Marquez twice before the end of the fight.
Calderon retained his title by a 12 round decision in his first defense, on September 5, over Lorenzo Trejo of Mexico, at Caguas, Puerto Rico. In his second defense, held at Bayamon, he defeated former world champion Alex Sanchez by a unanimous twelve round decision.
On March 20, 2004, he retained the championship with an eleventh round knockout win over former IBF world champion Edgar Cardenas, in Guaynabo.
Before that fight, Calderon obtained his high school credit diploma. Cesar Rey, director of the Puerto Rican school department, hoped Calderon could become an example to Puerto Rican youth.
Calderon as a professional is undefeated, with 19 wins and 4 of those by knockout.