Abstract: A chair arm mounted computer accessory support assembly that includes a support plate and a chair arm engaging assembly. The support plate has an upper surface for supporting a computer accessory and a lower surface for supporting the support plate on an upper surface of a chair arm. The chair arm engaging assembly is securely attachable to the lower surface of said support plate and is operably engageable with lateral surfaces of the chair arm to provide lateral support of the computer accessory support assembly relative to the chair arm. The chair arm engaging assembly includes a pair of side panels securely attachable to the lower surface of said support plate; and fastening means operatively associated with the pair of side panels for securing the pair of side panels on opposing sides of the chair arm.