Arena Naucalpan 26th Anniversary Show

The Arena Naucalpan 26th Anniversary Show was a major annual professional wrestling event produced and scripted by the Mexican professional wrestling promotion International Wrestling Revolution Group (IWRG), which took place on December 21, 2003, in Arena Naucalpan, Naucalpan, State of Mexico, Mexico. As the name implies the show celebrated the 26th Anniversary of the construction of Arena Naucalpan, IWRG's main venue in 1977. The show is IWRG's longest-running show, predating IWRG being founded in 1996 and is the fourth oldest, still held annual show in professional wrestling.

In the main event of the anniversary show, long time rivals Cerebro Negro and Avisman I both put their hair on the line as they wrestled in a best two-out-of-three-falls Lucha de Apuestas, or "bet match". The match saw Cerebro Negro defeat his opponent, leaving Avisman I bald as a result. On the under-card several Consejo Mundial de Lucha Libre wrestlers appeared on the show, including El Dandy, Negro Casas, Perro Aguayo Jr. and Scorpio Jr. facing off in a Fatal four-way match.