Cats can eat celery, and it is safe for them in moderation. Celery can even provide some health benefits such as antioxidants, fiber for digestion, hydration due to its high water content, and vitamins like A, C, and K. However, because cats are obligate carnivores, celery should only be given as an occasional treat and not as a primary part of their diet. It is important to serve celery in small, bite-sized pieces to prevent choking and avoid any seasoning or additives that could be harmful. Too much celery can cause stomach upset or diarrhea due to its fiber content. Celery seeds should be avoided unless advised by a veterinarian. Overall, celery can be a crunchy, healthy snack that some cats may enjoy occasionally.