Reports from English media, including BBC and Sky Sports News, stated that the former England striker will take over from stand-in manager Chris Hughton.
Interim boss Hughton has been in charge of the Magpies since manager Joe Kinnear suffered a heart problem in February, and the team slipped down to 18th place under the former.
Kinnear is recovering from triple heart bypass surgery and a return to the bench is unlikely for the 62-year-old.
Shearer, 38, has been repeatedly linked with the Toon job since retiring in 2006, but the BBC TV pundit was not tempted by the club's interest.
Throughout his ten-year stint at St. James' Park, Shearer hit a club record of 206 goals for Newcastle.
Newcastle are yet to make an official announcement regarding the news.