Yes. Both are even-toed ungulate mammals, or artiodactyls. Both are also ruminants, meaning they have s stomach that has evolved into several different compartments to help them digest food. In contrast, camels, pigs, and hippos are also artiodactyls, but they are not ruminants. That means deer and cows are more closely related to each other than either of them is to pigs, hippos, and camels.