Abstract: A method for operating a pulsed laser system includes the steps of pumping a laser resonator of the pulsed laser system by means of a pump source in order to generate operating laser pulses at an operating energy level; and coupling the operating laser pulses with a focusing element into an optical fiber. A step of cleaning the optical fiber by means of cleaning laser pulses is performed prior to generating the operating laser pulses. The laser resonator of the pulsed laser system is pumped by means of the pump source in order to generate the cleaning laser pulses at one or more cleaning energy levels between a laser threshold and the operating energy level.