Last year's NL Cy Young Award winner, Lincecum is 10-2 with a 2.33 ERA for the San Francisco Giants. He will get the ball Tuesday night at Busch Stadium, NL manager Charlie Manuel announced.
Lincecum made the All-Star team for last season's game at Yankee Stadium but was unable to pitch because he was ill.
"This is a great accomplishment for me," Lincecum said, his long, shaggy hair protruding from under a black knit cap. "I think tomorrow the big thing is going to be just getting to the field. And after that, just getting on the field."
Halladay, 10-3 with a 2.85 ERA for the Toronto Blue Jays, was chosen by AL manager Joe Maddon.
This is Halladay's sixth All-Star appearance, but his first chance to start -- and it could be his final trip in a Toronto uniform.
Blue Jays general manager J.P. Ricciardi said last week he'll listen to trade offers for the 2003 AL Cy Young Award winner, who is signed through 2010 and would have to agree to a deal.
At a news conference Monday, broadcaster Bob Costas called Halladay a member of the Blue Jays "at least for the moment," which drew a round of uneasy chuckles.
"It's tough. Obviously, I'm somewhere that I enjoy being and have spent my entire career. There's a lot, I think, that goes into it," Halladay said. "I think as a player, there's that will to win, that will to do it in October and basically that's what all of this has been about. I would like that chance. I'm not saying it won't be Toronto. You'd like to be three games up in first place and not have to deal with it."
Lincecum and Halladay each pitched Thursday, so both will be on their regular four days of rest.
In his most recent outing against San Diego, Lincecum carried a no-hit bid into the seventh inning and won his fourth straight outing.
Halladay, who has won more games than any other major league pitcher since 2002, has made three starts since returning from a stint on the disabled list with a groin strain. Maddon's Tampa Bay Rays are 5-3 against the two-time 20-game winner over the last two-plus seasons.
"I see him way too often," Maddon said.
"I wanted a guy that had played center field, was a true center fielder to put out there," Manuel said.
Florida shortstop Hanley Ramirez will lead off for the NL, followed by Philadelphia second baseman Chase Utley, St. Louis first baseman Albert Pujols and Milwaukee slugger Ryan Braun in right. Raul Ibanez of the Phillies will be in left and bat fifth, in front of Mets third baseman David Wright, Victorino, Cardinals catcher Yadier Molina and Lincecum.
Lincecum, a boyish-looking right-hander, is tied for the major league lead with 149 strikeouts. He was asked if he would take any precautions to make sure he doesn't get sick again this year. He said he would load up on fluids to stay hydrated and have Giants teammate Matt Cain "put a leash around my neck, keep me in a room."
For the AL, Seattle right fielder Ichiro Suzuki leads off and Yankees shortstop Derek Jeter is in the No. 2 hole. Minnesota catcher Joe Mauer bats third, followed by New York first baseman Mark Teixeira, Boston left fielder Jason Bay, Texas center fielder Josh Hamilton, Tampa Bay third baseman Evan Longoria, Toronto second baseman Aaron Hill and Halladay.
"It's just a great honor for me and I'm extremely excited," Halladay said. "A highlight moment for me in my career, so thank you."
Hill will start in place of Boston's Dustin Pedroia, last year's league MVP. Pedroia's wife, Kelli, is seven months pregnant and has been in the hospital since Monday with complications.
Halladay was chosen to start over Kansas City ace Zack Greinke, among others. Greinke is 10-5 with an AL-best 2.12 ERA.
"I think Doc over the last several years has demonstrated to be possibly the best pitcher in the American League," Maddon said. "Just based on this season and a body of work, I thought that he deserved the nod."