Dogs can safely eat watermelon as long as the seeds and rind are removed. The flesh of the watermelon is a healthy, hydrating treat packed with nutrients like vitamins A, B6, C, potassium, and fiber. However, the seeds can cause intestinal blockage and the rind can cause gastrointestinal upset, so both should be avoided. Feeding watermelon in moderation is recommended to avoid stomach upset, especially due to its natural sugar content. It can be given in small chunks, frozen, pureed, or blended with plain yogurt for a cooling summer treat.