Norma Rae Webster is a minimum-wage worker in a cotton mill that has taken too much of a toll on the health of her family for her to ignore their poor working conditions. After hearing a speech by a New York union organizer, Reuben Warshowsky, Norma Rae decides to join the effort to unionize her shop. This causes conflict at home when Norma Rae's husband, Sonny, says she's not spending enough time in the home.
Despite being pressured by management, when confronted, Norma Rae takes a piece of cardboard, writes the word "UNION" on it, stands on her work table, and slowly turns to show the sign around the room. One by one, the other workers stop their mill machines, and eventually, the entire room becomes silent. After all the machines have been switched off, Norma Rae is taken to jail but is freed by Reuben.
She then decides to talk to her children and tell them the story of her life. After discussing it with Reuben, Sonny tells Norma there's no other woman in his mind and he will always remain with her. Norma Rae then successfully orchestrates an election to unionize the factory, resulting in a victory for the union. Finally, Reuben says goodbye to Norma; despite his being smitten with her throughout the movie, they only shake hands because he knows she is married and loves her husband, and Reuben heads back to New York.