The invention discloses an ink jet printer nozzle anti-scratch device structurally comprising an anti-scratch ink jet printer, a touch screen, a data transmission connector, a data controller, a handle, a battery and an ink box. The anti-scratch ink jet printer is composed of an ink jet head, a nozzle, a cross bar, an anti-scratch device and a baseplate. The ink jet printer nozzle anti-scratch device has the effects that, through the anti-scratch device, when packing materials are printed through the ink jet head, irregular protrusions of the packing materials are not in contact with the nozzle, so that printing scratch is avoided; thus, the problem that the packing materials and cleaning agents are wasted due to the printing scratch caused by the irregular protrusions of the packing materials is solved; through a regulating mechanism, a handheld ink jet printer can be steadily and directionally moved on pipes in different diameters for ink jet; and thus, the problem that the handheldink jet printer for printing the packing materials can not be steadily and directionally moved on the surfaces of pipes in different diameters for printing is solved.