The Latin diva is said to have flown into a rage after she asked for a double espresso and was told that they couldn't make her one.
J.Lo, famed for her outrageous demands, took out her frustration on the stunned stewardess, hurling a torrent of hurtful insults at her.
The unnamed hostess is quoted on website AirlineCrew.net as saying: "She yelled at me because I could not make her a double espresso and then she told me my shoes looked cheap."
Lopez has also been added to an online blacklist called the "S****y Tipper Database" after she left a tip of just $1.27 on $350 restaurant bill in New York.
Meanwhile, Lopez has said she felt "compelled" to make her new movie - the upcoming biopic "El Cantante."
The singer-and-actress decided to make the film - which tells the story of Hector Lavoe, the man who is credited with bringing salsa to the US - after his widow begged her to take on the role.
She explained: "Once I read the script, I knew there was something about his life that was compelling to watch."
Hector - who committed suicide in 1993 by jumping off a building following a long running battle with drug addiction - is played by J.Lo's husband Marc Anthony.