The `I`m Outta Love` singer has decided to legally end her marriage to bodyguard Wayne Newton, citing irreconcilable differences, according to website RadarOnline.com.
The couple - who had no children - married in April 2007, but didn`t sign a pre-nuptial agreement.
Anastacia - who overcame breast cancer in 2003 - had previously spoken of her happiness at being married to Wayne but admitted it may not last forever.
She said: "There is a totally different vibe being married. I have wonderful security and hope we`ll grow old together. I`ll be sitting there with my crows feet and about two feet shorter. I really love being married.
"I`m not claiming I`m going to make it forever. I`m just saying that I`m going to try. We both have no idea what the situation is going to be like in ten years."
The 41-year-old star also said she and Wayne had decided not to have kids together as she was happy being a stepmother to his two sons.
She said: "Wayne and I have chosen not to have children. My husband has two boys already that I`ve grown very close to. It`s an aspect of my life that I`ve chosen not to explore."