A circuit board assembly structure and wave-guide devices thereof are used for assembling a circuit board on a shell wall. Each wave-guide device comprises a fixed column and a conductive spacer. The fixed column is combined on the shell wall and can be used for embedding the fixing holes on a circuit board and supporting the circuit board in an appropriate height. The conductive spacer is equipped with a substrate and at least two spring plates; wherein, the substrate can axially move along the fixed column and clings to the conductive layer on the bottom surface of the circuit board; the two spring plates extends from the edge of the substrate to be contacted with the shell wall. A plurality of fixed fasteners are arranged on the shell wall and used for embedding the corresponding edge of the circuit board so as to prevent the fixing holes of the circuit board from detaching the fixed column to the outward axial direction.