Assistant manager Gordon Young will take charge of the team on an interim basis and could be in the dugout for the trip to face Ross County on Saturday.
In a statement released by Falkirk FC tonight, the board of directors thanked Hartley for all of his efforts in charge of the club.
The 41-year-old leaves the club after Saturday's 3-0 defeat against Queen of the South at The Falkirk Stadium, which saw persistent protests against the manager from supporters.
Falkirk had no shots on target in the match, with Queens racking up 27 efforts on goal. The defeat left the Bairns bottom of the league after three Championship matches.
The search for a new manager starts with immediate effect but there is no indication as of yet when a new manager will be in place.
One thing is for sure, the new boss will have 16 summer signings to gel together - with Hartley having been given license to completely overhaul the squad this summer.