The bone fragments were discovered in the Carse of Gowrie, a stretch of farmland along the Firth of Tay, in September. A spokesman for the Crown Office said DNA tests have confirmed the identity of Adam Alexander, who was 38 when he disappeared 13 years ago from his home in Errol, The Scotsman reported.
Thomas Pryde was sentenced to 10 years in 2010 after he admitted killing Alexander with an iron bar and then, in a panic, hiding the body. The bones were found in the area where Pryde had said he buried his friend in a shallow grave.
The Crown Office said no new charges would be brought against Pryde, who was convicted of culpable homicide and hiding the body.
Alexander's disappearance remained a mystery for several years. Police questioned Pryde after his estranged wife told them he had admitted the killing while the couple were on vacation in Greece.
The body was near the Errol brickworks.