The invention discloses a clamping and limiting device for a PCB, which comprises a clamping platform, wherein a concave table is formed on the clamping platform, a notch is formed in the clamping platform, a supporting plate is fixed to the notch, a pushing air cylinder is fixed to the supporting plate, a lower rack plate is fixed to the pushing air cylinder, a pushing block is fixed to the lowerrack plate, the lower rack plate is meshed with a lower gear, the lower gear is meshed with an upper gear, the upper gear is meshed with an upper rack plate, a linkage rod is fixed to the upper rackplate, and a pull rod is fixed to the linkage rod; a connector is fixed on the pull rod, a driving rod is inserted into the connector, an arc-shaped guide groove is formed in the driving rod, a connecting shaft is inserted into the guide groove, the two ends of the connecting shaft are inserted into the connector, a pressing rod is arranged on the upper side of the driving rod, a pin shaft is inserted into the guide groove and fixed to the pressing rod, a pressing strip is arranged on the lower side of the driving rod, a connecting column is formed on the upper end face of the strip, and a pressure spring is fixedly inserted into the connecting column in a sleeved mode and fixed to the pressing rod.