The reality stars, whose real names are Nicole Polizzi and Jenni Farley, have recently been photographed in Jersey City with two of JWoww's dogs.
The animals, Bella and Noel, have been dyed pink and purple.
However, PETA told E! News that treating the dogs' fur that way could distress the pets.
"Dying a companion animal's fur causes the animal stress and can lead to complications or allergic reactions that endanger the animal's health," a spokesperson said. "Our dogs and cats love us regardless of how we look; we should extend the same kindness to them."
Earlier today, PETA denied that it was responsible for an incident which saw Kim Kardashian covered with flour on a red carpet, allegedly because she has been seen wearing fur.
However, the organisation added: "Whoever threw that flour may reach her when our polite appeals did not."