The branch says it needs new homes for the adult cats to make space for the kittens it is expecting to receive.
It supports cats and kittens across the city, covering postcodes MK1 to MK19 and MK46.
A spokesperson for the branch told the Citizen: "All rescues get busy this time of year and Cats Protection Milton Keynes is no exception!
"We have 40 cats and kittens in our care, with some cats having spent several months waiting for homes.
"Stormie, for example, has been waiting for over 150 days!
"It's important they get adopted soon so they can get settled with their forever family, and so we can free space to accept other cats desperate to come into our care.
"Mittens and Tinkerbelle could suit most homes, and Mittens may even be able to live with another cat.
"Stormie is looking for a pet-free and child-free peaceful home.
"We know the right family is out there for all of them!"
Applications to adopt the cats must be made through the branch’s website, but first have a look through our gallery to find out a bit more about these lovely cats in search of new owners and a happy home.
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5. Mittens
Mittens, who is described as a good all-rounder of a cat, knows how to use a cat flap and would like outdoor access in his new home Photo: Fosterers of Cats Protection Milton Keynes
6. Stormie
Stormie, aged nine, a grey tabby, has been with Cats Protection for more than 150 days Photo: Fosterers of Cats Protection Milton Keynes
7. Stormie
When not napping or snoozing, Stormie loves chasing her tail Photo: Cats Protection
8. Stormie
Stormie is looking for a calm and quiet home with no other pets or children, and is best suited to a peaceful environment and experienced cat owner Photo: Fosterers of Cats Protection Milton Keynes