Prone position is a body position in which one lies flat with the chest down and back up.

The word "prone," meaning "naturally inclined to something, apt, liable," has been recorded in English since 1382; the meaning "lying face-down" was first recorded in 1578, but is also referred to as "lying down" or "going prone."

"Prone" derives from the Latin pronus: "bent forward, inclined to," from the adverbial form of the prefix pro- "forward." Both the original, literal, and the derived figurative sense were used in Latin, but the figurative is older in English.

In anatomy, the prone position is a position of the body lying face down. It is opposed to the supine position which is face up. Using the terms defined in the anatomical position, the ventral side is down, and the dorsal side is up.

With respect to the forearm, prone refers to that configuration where the palm of the hand is directed posteriorly, and the radius and ulna are crossed.

In competitive shooting, the prone position is the position of a shooter lying face down on the ground. It is considered the easiest and most accurate position as the ground provides extra stability. It is the starting position in three positions events. Currently the Olympics only have one purely prone event, the fifty meters men's rifle prone. Both men and women also have the fifty meters rifle three positions. Many video games (particularly first-person shooters) allow the player character to go into the prone position.