"This cannot be happening in today's environment. We will not tolerate our profession being objectified in a sexist manner," APFA National President Lori Bassani said in a statement.
The union is demanding an investigation into American Airlines' involvement with the performance.
The Transport Workers Union also released a statement, claiming the airline had a new strategy: "Destroy blue collar America and expose air travellers to potential disaster by fixing AA planes on foreign soil, while simultaneously sexualising and degrading their own flight attendants."
American Airlines have denied any involvement in the "customer-organised concert" and said it "was not sanctioned by the airline".
"This was not an American Airlines event," the airline said in a statement.
"We did not have any say about the content of the event, nor did we preview any of the agenda.
"Additionally, we were particularly upset to see our logo on the screen as the skit was performed."
The airline added that the customer who posted the video had complied with a request to remove it.
The Dallas Morning News also spoke with the person who recorded the video, who confirmed it was not organised by the airline.
"This was just a group of friends who happen to share a love of aviation and routinely fly American Airlines, having a good time, nothing more," he said.