A control device of connection studs of a computer includes a plurality of hexagonal grooves which are punched at different distances on a base plate of a computer casing. The groove is provided with a through-hole, hexagonal heads of a set of studs are loosely fitted into the hexagonal grooves, and rods of the studs are loosely transfixed into the through-holes, in order to screw with a circuit board of different size, such that a number of studs to be actually used for screwing can be effectively controlled, and an interference from the unnecessary studs, the circuit board, or other parts can be prevented.