Can Cats Eat Tuna?
Last reviewed October 2026 · Based on 2 published veterinary sources (listed below)
Small amounts only
A small piece of plain tuna packed in water is fine as an occasional treat. Human tuna is not a complete diet for cats: fed often, it can crowd out nutrients cats need and adds mercury. Some cats also get so fond of it they refuse their regular food.
How to offer it safely
- Plain, packed in water, no salt, oil, onion or garlic
- A teaspoon or two, no more than occasionally
- Treats should be under 10% of daily calories
Avoid
- Tuna in brine or seasoned tuna
- Daily tuna as a meal replacement
- Raw fish fed often (can destroy vitamin B1 / thiamine)
This guide is general information, not a diagnosis. If you're worried about your pet, call your vet or an emergency clinic.