Alan Davies and Copstick both agreed that Parker had been a disappointment in all three gigs so far in the competition, but Copstick took things further, describing the 37-year-old as "quite s**t".
"Cole, I think you're quite s**t. I've seen you three weeks on the trot and I don't think you are a good comic and I don't think you can read a room," she said.
"Your comedic ego has been writing cheques that your talent can't cash, obviously for many, many, many years."
Copstick described rival comic Rudi Lickwood as "too old" and "too ugly", but the judges gave him another chance to improve in the competition.
Speaking afterwards, a deflated Parker said: "I think comedy is objective, it's like music and not everyone likes every type, so fair enough. I had a good show."
Show Me The Funny continues next Monday at 9pm on ITV1.