Plate clamping fixture

The invention discloses a plate clamping fixture which comprises a supporting frame arranged on a portal frame, wherein a front clamping piece and a rear clamping piece fit with the front clamping piece are arranged at the lower end of the supporting frame; the front clamping piece is fixed at one side of the supporting frame; the rear clamping piece is movably arranged at the lower end of the supporting frame; the rear clamping piece is connected with a driving component, and is driven to move forward and reversely at the lower end of the supporting piece by the driving component; the driving component comprises a host drive, an auxiliary drive and a circularly rotating driving belt; and the driving belt is jointly driven by the host drive and the auxiliary drive. The plate clamping fixture has the advantages of simplicity and convenience in operation, high practicability, and flexibility in use; and a chain can be tensioned to move forwardly, to be kept tightened, and to be locked by the auxiliary drive, so that an augmenting force is applied to the rear clamping piece to clamp a plate, and the clamping stability is improved.