Gwynn, who was on Wheaties once before in 1997 with six other outfielders, said: "I've been retired for 5 1/2 years now and I was on the Wheaties box once before ... and it's taken this long to be on the box by myself. I couldn't have picked a better time, going into the Hall of Fame. It's been an incredible year.
"Wheaties was a big thing in the Gwynn household."
In 10 days, Gwynn will be inducted into the Baseball Hall of Fame in Cooperstown, N.Y., along with Cal Ripken Jr.
Gwynn, better known as "Mr. Padre" in San Diego, spent his whole 20-year Major League career with the Friars. Gwynn's career spanned 15 All-Star selections, eight National League batting titles and over 3,000 hits.
Gwynn came to the unveiling wearing an orange hat with Wheaties scribbled on it.
Long-time Padres broadcaster Jerry Coleman introduced Gwynn as, "One of the greatest players that ever lived. I'm thrilled to death to be here."
Coleman, who has never asked for an autograph in his life, did so on Thursday.
Gwynn obliged by signing a WHEATIES box with a blue Sharpie.
The image on the box is a side portrait of Gwynn hitting in his blue, pinstriped Padres uniform. Gwynn always signs autographs with either a black or blue Sharpie. It all depends on the uniform. He signs in blue when it's a photo of him in his blue uniform and black when he's wearing his brown uniform. Although he used to sign with a brown Sharpie before black ones existed.
"That's how I can tell," Gwynn said from the real autographs and the phonies.
Gwynn said, "They picked a good picture" to put on the Wheaties box.
So what did his mother, Vendella, think of this accomplishment?
"I was telling her about it the other day, that I was going to be on a Wheaties box and she started laughing," Gwynn said.
The 5-foot-11 Gwynn posed for pictures beside the huge cardboard facade, which towered over him, but just barely.
After all the cameras were turned off, Gwynn talked about next week's induction into the Hall of Fame.
"Actually, I'm excited and nervous at the same time," Gwynn said. "I'm really looking forward to finally getting there.
"We've gone 6 1/2 months of waiting in anticipation. I'm kind of at the point where I'm anxious to get there and see if I'm going to be able to compose myself or break down and start crying. It's been a long week and I think I'm ready."
Tara Johnson, from Wheaties public relations, said this special-edition box is being shipped all over the nation, and admitted they might be selling out in San Diego.
Gwynn teamed up with Wheaties in its Fit to Win Challenge. Gwynn was a part of its 12-week online program that aimed consumers to eat healthier.
After the press conference was finally over, Gwynn still was going to return to PETCO Park later in the day because he is working the Padres' series opener against the Phillies in the broadcaster's booth.
Gwynn, who already has a street named after him, Tony Gwynn Drive, and had his No. 19 uniform retired by the Padres, will be honored again on Saturday with a statue in PETCO's Park at the Park.
"It's kind of weird. I got a ballpark named after me in San Diego State, I have a street out here, Tony Gwynn Drive, and now I have a statue out in the Park at the Park to go along with my retired number on top of the scoreboard."
"Out of all the stuff that's going on this year, this is up there and I'm really excited about it."
Gwynn, who finished his career with a .338 batting average, retired in 2001.
He will leave next Thursday for the Hall of Fame induction ceremony, and after that a vacation. Gwynn stayed mum on the destination, although he said he would be going to Milwaukee to watch his son, Tony Gwynn Jr., play with the Brewers.
Gwynn has not finished writing his speech for the ceremony. He has things he wants to talk about, and admits he may get emotional.
Maybe if he walked to the podium with a bat he might feel a bit calmer about the whole situation.
"The thought has crossed my mind," Gwynn said.
Elizabeth Botello is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.