Chelsea's winner in the fifth minute of stoppage time sent Maresca into a frenzy and he raced along the touchline at Stamford Bridge to celebrate wildly with his players, earning a second yellow card and a dismissal from referee Anthony Taylor.
"It was alleged that the manager acted in an improper manner and/or used abusive and/or insulting words and/or behaviour during the fixture, which led to his dismissal around the 96th minute," the FA said in a statement.
"Enzo Maresca subsequently admitted the charge and accepted the standard penalty."
Maresca will miss Chelsea's next Premier League game away at Nottingham Forest on Saturday. Chelsea are seventh in the standings with 11 points, five points behind leaders Arsenal.