The invention discloses an online and labeling device for a surface defect. The online testing and labeling device for the surface detect comprises a base plate, a winding bracket, an idler, a driving wheel bracket, a corner seat, a paper pressing wheel seat, an unwinding socket, a
phototube, a paper pressing device, a labeling band, a
stepper motor, a reducing motor, a reducing motor seat, a
stepper motor seat and the like, wherein a
signal receiving device used for receiving an operation
signal transmitted from a testing host is arranged on the
stepper motor; and the
signal receiving device starts the
stepper motor and drives each component of the labeling device to operate by receiving an operation command transmitted from the testing host, so that labeling operations can be finished accurately. The online testing and labeling deice for the surface defect has a small volume, light weight, and high labeling accuracy, and can be used for effectively preventing
external noise and
clutter interferences, and realizing continuous or discontinuous
label paper labeling; therefore, the online testing and labeling device for the surface defect is particularly suitable to be used for labeling operations of online testing of the surface defect on a
production line.