The 35-year-old is wanted as a mentor to younger forwards at the club and is open to the idea of moving to Edinburgh.
St Johnstone want to keep MacLean but cannot compete with Hearts financially. He has made 30 appearances and scored five goals for the Perth club so far this season but is out of contract next month.
The player is seen as an experienced campaigner who can be a positive influence on the teenagers who emerged from the Riccarton youth academy over the last year.
Hearts feel an older head in the striking department is important for next season, with youngsters Aidan Keena, Rory Currie and Anthony McDonald all still learning their trade up front.
MacLean was previously on trial at Riccarton in January 2010 but the Tynecastle hierarchy chose not to offer him a deal at the time.
As his St Johnstone contract nears its expiry, he could have the chance to join Hearts if all parties agree terms.