The verdict means that David Moyes will be without the Argentine for tonight’s Carabao Cup quarter-final clash with Arsenal at the Emirates Stadium.
The 24-year-old went down under the challenge of Erik Pieters on Saturday in the 3-0 win at the bet365 Stadium, to controversially earn a penalty.
Mark Noble converted from the spot as the Hammers cruised to a 3-0 victory, with further goals from Marko Arnautovic and Diafra Sakho.
A three-person panel from the Independent Regulatory Commission met on Monday and unanimously agreed that Lanzini had successfully deceived the match official.
The East London club decided to launch an appeal against the decision, which was fast-tracked by the FA, however it was unsuccessful meaning the ban stands.
Lanzini will now also miss West Ham’s Premier League clash with Newcastle United on Saturday afternoon, which will frustrate him after providing two assists at the weekend.
Moyes wasn’t very happy yesterday with the FA’s decision to charge the player.
He said: “It is clear to see the defender makes an attempt to go for the ball and doesn’t get it. From my point of view, they are going against the referee [Graham Scott], whoever the panel were.
“The Goals on Sunday panel all said it was a definite penalty.
“I think it’s strange that three people on Sunday thought it was a penalty and three people today [Monday] think it probably wasn’t.”
Lanzini is the second player to be banned for simulation this season, after Everton’s Oumar Niasse who earned his side a penalty in the 2-2 draw with Crystal Palace at Selhurst Park in November.