The 31-year-old died in police custody in May after an incident in a Kirkcaldy street.
Mr Bayoh's family claim they were given five versions of what happened to him.
The Lord Advocate will now consider the contents of the report. PIRC said it would continue to pursue evidence.
A spokesman for PIRC said: "The Police Investigations and Review Commissioner has now submitted an interim report to the Crown Office on its independent investigation into the circumstances surrounding the death of Sheku Bayoh on 3 May 2015.
"Our team of experienced and skilled investigators have gathered evidence, taken statements from witnesses and recovered productions and continue to investigate complex lines of inquiry.
"The Commissioner will continue to pursue further expert evidence in relation to the cause of death and is working closely with the Crown Office in this regard.
"The Lord Advocate is now considering the interim report."
An interim report by the Police Investigations and Review Commissioner (PIRC) into the death of Fife man Sheku Bayoh has been handed to the Crown Office.