Abstract: A method of protecting eyes from welding rays in arc welding and an apparatus therefor are disclosed which are capable of closing a filter plate over a period from right before the generation of arc welding rays to the termination of the generation to fully intercept the rays, to thereby effectively protect the eyes of an operator from the rays. The invention is constructed in a manner such that a controller carries out the on-off control of a voltage applied from a filter power source to a PLZT filter plate depending upon a signal supplied from a detection circuit thereto when the detection circuit detects a built-up current occurring in a welding current, to thereby carry out the actuation of the filter plate.