Caron Butler -- I Worry About Lamar Odom ... I Want to Help

NBA star Caron Butler says he wants to help Lamar Odom conquer his demons -- and has reached out to his former teammate several times -- telling TMZ Sports, "I worry about him."

Butler appeared on "TMZ Hollywood Sports" to talk about his new book "Tuff Juice" -- in which he touches on how he overcame his own issues (arrested 15 times as a kid, drug dealing, etc.) to make it to the NBA.

And with Odom's well-documented personal issues, we had to ask if he's tried to extend a helping hand to his longtime friend.

Check out the clip ... Butler makes it clear he still cares for Odom and wants to help him get his life back on track ... there's just one problem, he can't seem to get a hold of L.O.

Still, Butler says he wants Odom to know he can always count on him for support.