It is not clear if Henry was aboard the yacht.
Authorities and medics were called to Rowes Wharf behind the Boston Harbor Hotel around noon, where the yacht was parked. Police then found a man in cardiac arrest.
More from CBS Boston:
Boston police spokeswoman Cheryl Fiandaca said officers found a member of the yacht crew in cardiac arrest. The man, who was about 30 years old, later died in what Fiandaca said was “an apparent suicide.”
Henry, 63, purchased the Red Sox in 2002 as part of a multi-franchise sale that put the Miami Marlins in the hands of Jeffrey Loria.
The Red Sox issued a statement Monday afternoon:
Earlier today, a crew member on the vessel, M/Y Iroquois, apparently took his life aboard the vessel docked at 30 Rowes Wharf. Mr. Henry and the members of the Boston Red Sox are saddened by the news and send deepest condolences to his family.