He will be introduced Friday at a news conference on campus.
"You know me," Garrett said in a phone interview Thursday. "I want to win. I want to win national championships and graduate our student-athletes."
Garrett, 71, served as USC's athletic director from 1993 to 2010, when he was replaced by Pat Haden in the wake of NCAA sanctions that resulted from scandal surrounding football player Reggie Bush and basketball player O.J. Mayo.
In June 2012, Garrett was hired as athletic director at Langston University, a historically black college in Oklahoma. He resigned last April.
At Cal State L.A., Garrett succeeds Dan Bridges, who announced in September that he would retire Dec. 31 after 10 years in the position.
Garrett, who grew up in Boyle Heights and attended Roosevelt High, will oversee an NCAA Division II program that fields teams in men's and women's basketball, soccer and track and field; baseball; and women's volleyball, tennis and cross-country. The Golden Eagles compete in the California Collegiate Athletic Assn.
Garrett said he was attracted to the position by the challenge and the locale.
"I've done it before, and Cal State L.A. is very much near the neighborhood where I grew up," he said.
Garrett said he was approached by Cal State L.A. President William A. Covino and Jose A. Gomez, the university's senior vice president and chief operating officer, regarding the position. The situation, he said, was similar to what he faced when he became USC's athletic director.
"I knew what it entailed," he said, adding, "We want to upgrade … and make it a destination."
Garrett said he would eventually like one or two sports to move to Division I. He does not officially begin his duties until January, but he will spend the next month doing "a lot of homework, so when Jan. 1 comes we hit the ground running."
One of his first orders of business will be meeting with coaches to explain his vision and expectations.
"Nothing personal, but if you don't win and you can't recruit, we have to go and find people that can," he said.