The reason why cats smell bad:
1. Is the cat's ear canal clean? If there is a lot of dark discharge, the cat may have ear mites, Malassezia, ear disease, or other ear infections.
2. The cat hasn't been bathed in a long time. It may have gotten dirty from other things, or it may have stepped in feces and smelled bad.
3. If you don't clean your cat's mouth regularly, bacteria can grow in the mouth and cause diseases such as periodontitis and gingivitis, resulting in an unpleasant odor from the cat's mouth.
4. If your cat has skin problems, check its fur and skin color to see if it is normal and if there are any black spots. If so, there may be parasites present.
5. If everything else seems fine, then you should check the anal glands. Don't assume only dogs have anal glands; cats also need their anal glands expressed regularly. If you frequently bathe your cat at home, you should pay attention to this.
6. Male cats have a stronger body odor during their heat cycle, which is how they attract mates. 
How to remove cat odor:
1. Cats should relieve themselves in a fixed place, and owners should clean up the excrement in the litter box in a timely manner to keep the litter box clean.
2. Brush your cat's fur regularly every day and bathe it periodically to keep its fur clean and dry.
3. Clean the cat's ears, as earwax is a cause of body odor in cats. Use a brush or ear pick to remove any dirt from inside the ears, then clean them with cotton balls soaked in saline solution.
4. Take your cat for regular check-ups. If your cat is sick, you will need to take it to a veterinary hospital for treatment.
