Abstract: An improved mouse cleaning apparatus having a cleaning ball for temporary insertion into the cavity formed on the underside of the mouse. In one embodiment, the cleaning ball includes a core which is encased within an outer shell of polymeric material such as a foamed rubber compound. This core may be metallic, polymeric, or made of another sufficiently dense material, and is provided to ensure that the cleaning ball is sufficiently heavy to properly roll in response to movement of the mouse across a mouse pad or the like. The core may alternatively be covered with absorbent fibers, which may be synthetic or organic in nature, rather than a polymeric coating. In another embodiment, the cleaning ball is made entirely of a polymeric or elastomeric material having sufficiently high weight and/or density or is sufficiently compressed such that a weighted core is not required.