When Kutcher and Moore were married, the 35-year-old actor would regularly tweet pictures of his wife and talk about their relationship on the micro blogging website.
But the "Two and A Half Men" star says he has learnt his lesson and won't be discussing his relationship with Kunis, reported Daily Mirror.
"I've learned that there are a lot of things in your life that really benefit from being private. And relationships are one of them. And I am going to do everything in my power to have this relationship be private," he said.
When asked about the current state of his relationship with Moore's three daughters, from her previous marriage to Bruce Willis, he said, "There are some things that are better left private. "Someone once told me, 'If anyone wants to be rich and famous, let them be rich first and see if they still want to be famous.