The milk snake (Lampropeltis triangulum) is a species of king snake. There are around 25 subspecies among the milk snakes, including the scarlet kingsnake (Lampropeltis triangulum elapsoides). The subspecies have strikingly different appearance, and many of them have their own common names. They are found from Canada to Ecuador.

Some milk snakes have a striking resemblance to a coral snake and use this mimicry (a type of mimicry called Batesian mimicry) as a form of self defence. However, the Eastern Milk Snake (Lampropeltis triangulum triangulum) does not resemble a coral snake; instead it tends to have similar markings to that of several other snakes, particularly the fox snake. There is enough distinction to make the Eastern Milk Snake fairly easy to identify.

Milk Snakes are much more opportunistic eaters than the fox snake or corn snake. They have been known to consume a variety of animals including rodents, eggs, birds, reptiles, amphibians, and invertebrates. Nevertheless the diet of an adult milk snake still primarily consists of rodents. They are nocturnal eaters and are often found during the day in old barns and under wood.

A common myth about the milk snake is that they suck the milk out of cow's udders. The myth is entirely false. The milk snake does not have the physical capabilities to suck milk out of a cow. Milk snakes are, however, frequently found in and around barns, making use of their cool and dark environments, and for the easily accessed populations of rodents to feed on. This proximity to barns, and therefore cows, gave rise to the myth.