Luis Ignacio Ayala (born January 12, 1978, in Los Mochis, Sinaloa, Mexico) is a Major League Baseball pitcher for the Baltimore Orioles. He is 6' 2" and weighs 190 lbs. and bats and throws right-handed.

In 1997, as a 19 year old, Ayala started playing in the Mexican Baseball League as a relief pitcher. He spent five years with Saltillo, where he was 10–3 with a 2.92 E.R.A. in 65 games. He was signed as an undrafted free agent by the Colorado Rockies in 1999 and spent time with their A ball team before the Rockies sold him back to Saltillo in 2001.

In 2002 he was purchased from Saltillo by the Montreal Expos. He played with the AAA Ottawa Lynx in 2002. At the end of the 2002 season, he was signed by the Arizona Diamondbacks, but two months later returned to the Expos as a Rule 5 pick.

He made his major league debut on March 31, 2003 for the Expos against the Atlanta Braves, working two innings of relief and allowing one run and four hits. His 10 relief wins that season were tied for 2nd in baseball and