A man who killed his wife and posted a photo of her dead body on Facebook has been found guilty of second-degree murder.

Derek Medina shot 27-year-old Jennifer Alfonso eight times during an argument in their Florida home.

The 33-year-old former amateur boxer, who claimed he acted in self-defence, admitted to the August 2013 killing in posts on Facebook.

A Miami jury returned a guilty verdict on Wednesday, one day after being handed the case.

Medina faces up to life in prison.

At trial, prosecutors said Medina fatally shot Ms Alfonso because she threatened to leave him.

Court records indicated the couple had a tumultuous relationship.

They were first married in January 2010, divorced in February 2012 and then remarried three months later.

Medina's defence, who deferred making an opening statement, argued that Ms Alfonso abused drugs, battered her husband and was involved in Satan worship.

They claimed Medina shot his wife after she attacked him a knife.

Afterward, he posted two messages on Facebook, acknowledging he had killed her.

"I'm going to prison or death sentence for killing my wife love you guys miss you guys take care Facebook people you will see me in the news," he wrote in the first post.

The next and final post, called "Rip Jennifer Alfonso", was a gruesome photograph showing a woman in a black leotard slumped on the floor.

The photo was up for more than five hours before Facebook removed the page.

(SKY)