Typically, whey protein powder is considered gluten-free as it is derived from dairy, which does not naturally contain gluten. However, it is possible for whey protein powder to be contaminated with gluten during processing or if ingredients containing gluten are added. It's important to check the ingredient list and look for a gluten-free certification on the product label to ensure that the whey protein powder is safe for those with gluten sensitivities or celiac disease.