The invention discloses a nozzle protective device for a continuous type printing production line and a control method, which can perform early warning on the thickness of the fabric and the foreign matter on the surface and can adopt a corresponding means to protect the nozzle from damage. The nozzle protective device comprises a pedestal, a guiding belt, CMYK four groups of printing units, a beam synchronization elevating system, a three point positioning mechanism, a rack, an A group detection mechanism and a B group detection mechanism. The CMYK four groups of printing units comprise a printing unit C, a printing unit M, a printing unit Y and a printing unit K; the beam synchronization elevating system comprises a left transverse beam, a right transverse beam and a servo motor; the three point positioning mechanism comprises a flat bottom groove, a conical groove, a V-shaped groove, a steel ball seat A, a steel ball B and a steel ball C. The invention can automatically detect the thickness and the abnormal surface of the fabric, effectively guarantees the safety of the nozzle, prolongs the service life the nozzle, avoids the shut-down adjustment and improves the production efficiency.