The Polish goalkeeper was shown a straight red in the second half at Upton Park as referee Chris Foy felt he impeded Diafra Sakho when the striker was running at goal.
It was a decision that angered Swansea manager Garry Monk, who claimed Sakho was guilty of a handball initially.
"It's obvious that he handles the ball to get past Lukasz, but I think the referee had already made his mind up and was adamant he was going to send him off," Monk told Sky Sports.
The Welsh club confirmed on Monday they will appeal the decision with a verdict expected ahead of Sunday's Premier League clash with Tottenham.
"Swansea City can confirm that the club will be appealing the red card issued to goalkeeper Lukasz Fabianski against West Ham on Sunday," read a statement on their website.
"The club officially informed the Football Association by today’s 1pm deadline."
