A spreader bar is a piece of equipment used in the practice of sexual bondage. At minimum it consists of a stiff bar, typically two to three feet long with attachment points for restraints at each end.

Worn on the wrists, a spreader bar serves to immobilize the hands of the wearer, allowing others the unrestricted use of the wearer's upper body. Worn on the ankles it both immobilizes the feet, preventing all but the most awkward walking, and also spreads the legs, allowing greater access to the wearer's genitals, backside, and legs.

Spreader bars may include extra attachment points along their length for collars, suspension play, or attachment via rope or chain to other hardware.