Other political and business leaders attended the dinner at the Chicago Cultural Center.
Before the dinner, representatives from the city of Chicago and members of the Korean delegation discussed business opportunities.
The visit took place just one day after the ratification of a free trade agreement between South Korea and the U.S.
A busy Friday in the Loop was made busier by security sweeps in preparation for Pres. Lee. He arrived late Friday afternoon from Detroit where he spent the day with President Obama at a GM plant in the Motor City.
"As you can see, President Lee is a pretty good politician. He knows how to get on your good side," Obama joked.
The South Korean told Detroit autoworkers that the trade deal will mean job security for them. The deal calls for a dramatic increase in South Korean imports of American cars, something Mr. Obama said was made possible by his administration's $85 billion bailout of GM and Chrysler in 2009.
"If Americans can buy Kias and Hyundais from Korea, then I know Koreans should be able to buy Fords and Chryslers and Chevys made right here in the United States of America," Obama said.
Korean American community organizers say there are 90,000 Korean Americans in the Chicago area.
On Chicago's North Side where the Korean American community first came of age, community members are excited by Pres. Lee's visit.
"This is kind of recognition of Chicago Korean American community by South Korean government. That is why they feel, finally we are recognized," said Sik Son, Korean American Resource and Cultural Center.
Mr. Son says Pres. Lee is well regarded by older Koreans here for his pro-American attitudes especially on free trade, a stance that has the term-limited leader somewhat at odds with the younger people of his country.
Still, the president's visit is a point of pride for Korean Americans who have grown their community across the US.
"Right now I think a lot of Korean Americans think that the better way to help Korea is to have more power of Korean Americans here in the States," said Son,
Some protesters denounced the visit what they say is the South Korean government's policy of deporting Chinese Falun Gong refugees back to China.