To provide a compound for polishing a barrel and a barrel polishing method capable of stably exercising the action of a surface active agent without depending on an amount of ion included in the water.

A polishing operation is executed in a state that works, abrasive stones, the water, the surface active agent, and an ion adsorbing agent (zeolite) capable of adsorbing a calcium ion and/or magnesium ion in the water and preventing the formation of smut during the polishing operation, are mixed inside a barrel polishing vessel, whereby the polishing operation of the works can be stably executed.