A layer cake (US English) or sandwich cake (UK English) is a cake consisting of multiple stacked sheets of cake, held together by frosting or another type of filling, such as jam or other preserves. Most cake recipes can be adapted for layer cakes; butter cakes and sponge cakes are common choices. Frequently, the cake is covered with icing, but sometimes, the sides are left undecorated, so that the filling and the number of layers are visible.

Popular flavor combinations include German chocolate cake, red velvet cake, Black Forest cake, and carrot cake with cream cheese icing. Many wedding cakes are decorated layer cakes.

In the mid-19th century, modern cakes were first described in English. Maria Parloa's Appledore Cook Book, published in Boston in 1872, contained one of the first layer cake recipes. Another early recipe for layer cake was published in Cassell's New Universal Cookery Book, published in London in 1894.