Owens Boomer Castleman (July 18, 1945 – September 1, 2015), better known by his stage name Boomer Castleman, was an American singer-songwriter and guitarist. He was from Farmers Branch, Texas.

He paired with Michael Martin Murphey in the 1960s pop group The Lewis & Clarke Expedition, which recorded a pop album in 1967 for Colgems, the label that released The Monkees. The band was said to have gotten the deal with Colgems through Murphey's, Castleman's, and bassist John London's associations with Michael Nesmith – a native of Dallas.

Following the demise of that band, he went forth as a solo artist. In 1975 he became a one-hit wonder, hitting the US charts with the single "Judy Mae", which peaked at #33.

Castleman was the inventor of the palm pedal, a device that allows guitar players to execute pedal steel-style string bends. He made his original prototype in 1968, and the device is now marketed under the name Bigsby Palm Pedal. The original patent has expired, allowing other vendors to market similar devices, but the Bigsby/Castleman version is the original.

Castleman founded the independent country music record label BNA Records which he later sold to BMG Music.