"Pay that man his money," Simms said, per the New York Post.
Beckham reportedly is seeking a new contract that will make him the highest-paid wideout in the game. He is set to play for $8.5 million in 2018 on the fifth-year option of his rookie deal.
"He is one of the best weapons on offense I've seen in the NFL in a long time," the 62-year-old Simms said. "(Pittsburgh Steelers wide receiver) Antonio Brown is great, but he's a different type of player. So is (Atlanta Falcons wideout) Julio Jones. I just look at Odell Beckham Jr. and, man, I don't know what to say."
Beckham does not come without issue, however.
The 25-year-old's maturity has been called into question as recently as this past season when he pretended to relieve himself like a dog while celebrating a touchdown during a Week 3 loss in Philadelphia.
During his career with the Giants, Beckham also has had "romantic" encounters with a kicking net, a high-profile feud with then-Carolina Panthers cornerback Josh Norman as well as punching a hole in the wall outside the locker room in Green Bay following a playoff loss to the Packers.
Simms, however, isn't putting much stock into those distractions.
"It's always a gamble," Simms said. "You want to win, you got to gamble. Nobody knows him better than they do. I've never heard a teammate or run into any of his teammates who ever tell me anything bad about him. He makes the Giants really relevant. He's one of the big names in the NFL.
"Old-timers and writers look at his antics and this and all that. We had a guy (Lawrence Taylor) who had some antics, too. We put up with him, and it worked out pretty well."
A three-time Pro Bowl selection, Beckham was limited to four games in 2017 before he was injured. Without their best offensive player, the Giants slumped to a 3-13 record last season while New York's offense ranked 31st in the league in scoring at 15.4 points per game.
Beckham has 313 catches for 4,424 yards with 38 touchdowns in four seasons with the Giants. He was named the 2014 Offensive Rookie of the Year.
"When you talk about Odell, you can say, 'They double cover him,' but you really can't make people understand what it really means and how it makes life easy for calling plays and designing plays," Simms said. "In this day and age there's so many formations and so many other things, they want to get Odell Beckham Jr. the ball, they're gonna find a way to get him the ball. I don't care what the defense does. ...
"You need zero distractions. You want him on your team, you know what he is and you know you're all-in this year. All right, so go all-in. You got to go all-in and that means you got to get Odell Beckham Jr. signed and not make it a big part of the whole offseason story on every TV show I have to watch. So get it over with."
A two-time Super Bowl champion, Simms spent his entire 14-year NFL career with the Giants. He was named the Most Valuable Player of Super Bowl XXI and is a two-time Pro Bowl selection.