Garza's return solidifies the Hawkeyes as a legitimate contender to win the Big Ten championship and national title. The program has not reached the Final Four since 1980 and has not won a Big Ten title since 1979.
"I love this place too much to leave it," Garza said in a Sunday news conference.
Garza, who lost the two-man race for last season's Wooden Award with former Dayton star Obi Toppin, will top every reputable list as a preseason All-American and the projected national player of the year.
College players who have entered the draft must withdraw by Monday to preserve their collegiate eligibility. Garza, who recently received an invite to the NBA combine, said he "felt strongly" he would have been drafted and said he had offers in Europe.
"It's been really strange and difficult with COVID-19," Garza said. "It added a lot of uncertainty. At the end of the day, I felt very confident that I wanted to come back and finish my career at the University of Iowa."