Coconut — Food safety facts
Feed with care · Dogs · full breakdown on the linked food page
Fresh flesh in small amounts is usually fine; coconut water is high in potassium and milk/oil are very fatty. Watch for upset stomach.
Short answer
Yes, a small piece of fresh coconut flesh is generally safe for a dog, though coconut water is high in potassium and the milk or oil is very fatty. Give only a tiny amount and avoid giving large quantities of coconut water, milk, or oil. Watch for signs such as vomiting, diarrhea, or a bloated belly. If any of those appear, call your regular vet for advice.