Can Dogs Eat Tuna?
Caution — a small amount of canned tuna in water, unsalted, is fine for dogs occasionally. Because of mercury build-up it should not be a routine; oily or salty cans and raw tuna are unsuitable.
Last reviewed: July 24, 2026
What to know
Tuna is a large fish high on the food chain, and mercury accumulates in its flesh. A fork or two of water-packed tuna now and then is fine; as a weekly routine the mercury load becomes meaningful. Keep portions even smaller for small breeds.
When choosing: water-packed, no or low salt; oil-packed adds pointless calories, and sauced versions add salt and additives. If fish treats are going to be regular, smaller species like cooked, boneless salmon or sardines are the better pick.
Frequently asked questions
How often can my dog have tuna?
Occasionally — a few small portions a month is reasonable. For regular fish treats, switch to low-mercury species.
My dog ate tuna cat food — is that a problem?
One stolen bowl is usually harmless, but cat food is too rich and unbalanced for dogs — do not let it become routine.
Related answers
Sources
This guide is based on publications from the following veterinary bodies. Where sources differ, we take the more cautious position; the final decision is always your veterinarian's.