PCB board card signal loss test fixture

The invention provides a PCB board card signal loss test fixture. The PCB board card signal loss test fixture comprises an SMA connector, an upper pressing plate, a lower pressing plate and a pressingand tightening mechanism; a mounting through hole is formed in the upper pressing plate; the SMA connector is vertically mounted on the upper pressing plate through the mounting through hole; the SMAconnector is provided with a mounting flange; the mounting flange is provided with at least two flange mounting holes; at least two flange mounting holes are provided with limiting columns; each limiting column and the corresponding flange mounting hole where the limiting column is mounted are coaxially distributed; the parts, located below the mounting flanges where the limiting columns are located, of the limiting columns are located below the upper pressing plate; the lower pressing plate is provided with limiting holes used in cooperation with the limiting columns; a PCB test board is pressed between the upper pre