The news conference will be streamed live on MLB.com at 9 a.m. CT.
Sveum, who turns 48 on Nov. 23, reportedly received a three-year deal with an option for a fourth year. He'll be the 52nd manager in Cubs history.
Sveum took over the Brewers as interim manager in September 2008 after Ned Yost was dismissed. The Brewers went 7-5, and rallied to clinch the NL Wild Card spot, but lost in four games to the eventual World Series champion Phillies in the NL Division Series.
"It definitely whet the appetite a little bit," Sveum said on Nov. 7 when he met with the media at Wrigley Field after his first interview with the Cubs. "I think we all want to do things, but until you get thrown in the fire, you don't know if it's the right thing for you, even if it's something you want to do.
"Once I got to manage that year, those 12 games and the four games in the playoffs, it was somewhere where I felt right at home and very comfortable doing," he said.
The Brewers did pass on Sveum twice when they named their next two managers.
"I moved on," Sveum said. "I knew it would happen someday that I would get an opportunity. I never lost hope for no means."
Said Brewers general manager Doug Melvin: "That was more a philosophical thing. We wanted to go with a new name and a new face from outside."
At the General Managers Meetings, Melvin said he talked to Sveum early Thursday, but the Cubs were still finalizing the deal.
"If he gets that job, I'm happy for him," Melvin said. "I think he's ready to manage and he gets to do it for a team he's familiar with."
Cubs president of baseball operations Theo Epstein would not comment on the manager search as he left the Pfister Hotel and the GM Meetings on Thursday.
"We've got our closer in the game," Epstein said. "We've got to get the 27th out."
The Cubs interviewed Sveum, Rangers pitching coach Mike Maddux, Phillies bench coach Pete Mackanin, Indians bench coach Sandy Alomar Jr., and Red Sox bench coach DeMarlo Hale. Maddux withdrew from consideration for family reasons.
Sveum, who played parts of five seasons in Milwaukee from 1986-91, a tenure interrupted by a major left leg injury, had been on the Brewers' staff since 2006 as a third-base coach, bench coach and most recently as hitting coach. He'll be the second former Brewer to take over a National League Central rival this week; Mike Matheny was named Cardinals skipper on Monday.
Sveum met with the Red Sox on Wednesday as well as the Cubs this week. Epstein and Cubs general manager Jed Hoyer met with Sveum on Tuesday night. On Wednesday night, Red Sox GM Ben Cherington said they were expanding their search and wanted someone with more managerial experience.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter@CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.