Slatko is a Serbian fruit preserve that consists of distinguishable, usually whole pieces of fruit that are doused in a thick, sugary syrup. It can be prepared with various types of fruit such as quinces, watermelon rinds, cherries, raspberries, strawberries, blackberries, figs, grapes, plums, prunes, and even rose petals, while sugar-based syrups can often be flavored with vanilla, lemon juice, cinnamon, or cloves.

Serbian slatko, which translates as sweet, is a sign of hospitality that is traditionally offered as a warm welcome to guests. It is always served in small glass bowls and the guests should customarily enjoy only a spoonful of the preserve.

A portion of slatko is usually accompanied by a glass of water and is typically followed by coffee and traditional plum brandy (rakija). Slatko is closely associated with the Greek spoon sweets, while similar preserves can also be found in Montenegro and Bulgaria.