The 25-year-old earned plaudits after helping England to their first World Cup semi-final since 1990 in this summer's tournament in Russia.
United manager Jose Mourinho is reportedly interested in signing Maguire and has tabled a bid thought to be in the region of £65m, but Puel is eager to keep one of his key players for the 2018-19 Premier League campaign.
"For me it's good for Leicester to keep a valuable player, and it's important to show good ambition for the next season," Puel told Sky Sports News.
"I can understand some speculation about our player because he has good attributes, but I am happy to keep him and hopefully start a great season.
"We lost Riyad Mahrez, who was a very good player for us. After Riyad it was important to keep our players and add some good players to strengthen the team."
Mourinho may have to look elsewhere to strengthen his defensive options, should Leicester be reluctant to sell, before the transfer window closes on Thursday. body check tags ::