Jell-O, stylised as JELL-O, is an American brand offering a variety of powdered gelatin dessert, pudding, and no-bake cream pie mixes. The original gelatin dessert is the signature of the brand. "Jell-O" is a registered trademark of Kraft Heinz, and is based in Chicago, Illinois.

Gelatin desserts are desserts made with a sweetened and flavoured processed collagen product (gelatin). This kind of dessert was first recorded as jelly by Hannah Glasse in her 18th-century book The Art of Cookery, appearing in a layer of trifle. Jelly is also featured in the best selling cookbooks of English food writers Eliza Acton and Isabella Beeton in the 19th century.