The invention discloses a solder mask hole plugging device for a PCB. The solder mask hole plugging device comprises a placing platform and is characterized in that fixing racks are arranged on two sides of the placing platform, two connecting rods are fixedly connected between the fixing racks, the two connecting rods are located on two sides of the fixing racks, the connecting rods are located above the placing platform, the lateral walls of the two connecting rods are provided with through slide grooves, a slide rod is arranged between the two connecting rods, two ends of the slide rod areslidably connected into the two slide grooves, a connecting block fixedly sleeves the slide rod, a hydraulic oil cylinder is arranged at the lower end of the connecting block, a silk screen printing machine is connected to the piston end of the hydraulic oil cylinder, an opening is arranged in the upper end of the placing platform in a penetrating manner, a base plate is detachably connected to the upper end of the placing platform, and the lateral wall of the base plate is provided with a plurality air guide holes in an equal-distance and penetrating manner. The solder mask hole plugging device is simple in structure, convenient to operate, capable of effectively fixing the PCB to prevent the PCB from moving during hole plugging and good in fixing effect.