The final episode of the show's ninth series aired earlier this month and has since racked up more than 100 complaints to TV watchdog Ofcom.
The objections concerned a 'funny quip' about cleft lip and palate made in the episode on May 3, which was watched by 4 million viewers.
Benidorm character Joyce Temple-Savage was seen describing singer Danny Tetley as someone with “the voice of a thirteen year-old girl and a face like a dropped pie”.
In an open letter to ITV following the episode, the Cleft Lip and Palate Association (CLAPA) said they were "extremely disappointed to hear of an ignorant and highly offensive comment."
They added: "As a scripted show, it’s almost unbelievable that this line made it through to the final cut of Benidorm without anyone taking issue. Unbelievable, and unacceptable. "
One of those lending her name to the outrage was TV star Carol Vorderman.
She tweeted the letter alongside the message: "I am patron of CLAPA. My brother Anton was born with a severe cleft lip and palate. I have witnessed abuse of those with cleft
"Therefore, I wholeheartedly endorse this open letter to @itv"
A total of more than 130 official objections were made to Ofcom but the regulator dismissed them this week, saying they "did not raise issues warranting investigation".
A spokesperson for ITV told The Sun newspaper about the complaints previously: “Danny is a very talented performer and hugely popular on the circuit. We were thrilled to have him on the show.”