Although the actions of felines are often a source of confusion and head-scratching, remember just one thing: When a cat lies on her back and shows her belly to you, it is usually a display of trust and feeling completely safe. Take the body language as the utmost kitty honor.
When a cat is lying on her back and her belly is visible, she's probably communicating to you that she's feeling totally happy, relaxed and content. She's in good spirits, and all is fine and dandy in the world -- at least for the moment, of course!
Apart from just showing pure, unadulterated happiness, a cat lying on her back and showing off her tummy is also displaying a very submissive and vulnerable behavior. If your cat is willing to be this "defenseless" around you, it may be a true sign that she trusts and feels safe around you. She knows that you're not going to do anything to harm her. After all, a cat showing her belly is in no way prepared to properly protect herself and handle a predator attack. Also look out for other hints of submission, such as the legs being spread apart.
Although a cat showing her stomach typically indicates trust and joy, that definitely isn't true 100 percent of the time. According to Ohio State University's Center for Knowledge Management, female cats occasionally employ the stance during the mating process. Thankfully, it's usually pretty easy to discern a mating cat from a merely happy one, so breathe a sigh of relief.
The Center for Knowledge Management also indicates that lying on the back can point to a playful, lighthearted mode in felines. If your little one all of sudden turns over onto her back, it may be a request -- or urgent demand -- for you to take out the feather wand or the stuffed catnip mouse, so get to it! Your fluff ball is waiting for you.
Vocalization may be able to provide a hint regarding what your cat's belly exposure may mean. According to the Humane Society of the United States, a growling cat on her back can even mean preparation to attack -- yikes. However, on the contrary, a purring feline on her back may actually be asking for you to stroke her tummy -- aww. Be warned, though, that not all purring cats appreciate tummy strokes when in this position. If your cat is simply relaxing and you interrupt her serenity by touching her belly, she may show her displeasure by biting or scratching you -- yikes!
Always use context when deciphering your kitty's body language motives. The difference between a growl and a purr is massive.