A promising breed, with a size warning attached
Great Danes are among the giant breeds more likely to succeed with cats. Most Danes have a moderate rather than intense prey drive, they are not bred to chase and grab small animals, and their default indoor pace is slow and settled. Many live genuinely fondly with cats, sharing sofas and following feline housemates around with loose, wagging interest. The warning is mechanical rather than temperamental: a Dane weighs many times what a cat does. A playful paw, a joyful bounce in a narrow hallway, or a chase up the stairs can injure a cat even when the dog means nothing but friendship. Good outcomes come from managing the size gap while the relationship forms, not from assuming a gentle breed makes supervision unnecessary.
The individual dog and cat decide it
Breed is only the starting point. A Dane raised with cats from puppyhood usually reads feline body language well and respects a hiss, while an adult rescue Dane with an unknown history may fixate on movement in a way that rules out free access for a long time, or permanently. The cat's character matters just as much. A confident cat who stands her ground and strolls rather than bolts rarely triggers chasing, while a nervous cat who fleets at every sound invites pursuit from even a mild dog. Ask the rescue or breeder directly how this specific dog behaves around cats, and if possible arrange a controlled meeting before committing. A dog who can look at a calm cat, then look away for a treat, is showing you the raw material you need.
Introductions that protect both animals
Start with scent before sight. Keep the cat's territory intact, let the Dane settle into the home behind a closed door, and swap bedding so each animal learns the other's smell alongside feeding and rest. Move to sight through a baby gate or a cracked door, with the Dane on a lead, rewarding calm glances away from the cat and ending sessions while everyone is still relaxed. Only when the Dane can hold a settle in the cat's presence should you try a loose lead in the same room, and free mixing comes last, supervised, with the cat always able to leave upward or through a cat-sized gap the Dane cannot follow. Never carry the cat to the dog or hold her in place for inspection. Forced closeness teaches both animals the wrong lesson.
Living arrangements for the first year
Design the house so success is easy. The cat needs vertical territory, a litter area the Dane cannot reach, since many dogs raid litter trays, and feeding spots safe from a very tall counter-surfer. Feed the Dane separately and keep his exuberant moments, arrivals, and play sessions, in areas where the cat is not trapped at floor level. Watch the specific danger moments: doorways, stairs, and garden chases at dusk, when a running cat is hardest for any dog to ignore. If chasing appears, go back a stage without frustration. Some pairs need weeks, some need months, and a small number of dogs should simply live with the gate as a permanent, workable arrangement rather than being pushed toward a friendship that is not safe.
One routine for two very different pets
Mixed-pet households fail most often on inconsistency: one person lets the Dane loose with the cat, another still enforces the gate, and the animals get conflicting rules. Writing down the current stage, the safe rooms, and each pet's feeding and retreat arrangements where everyone can check them keeps the plan intact on busy days and for sitters. Each animal keeps a separate profile, and KinsLe Family Sharing lets you give relatives you pick access to both profiles, the Dane's and the cat's alike.