<p>The present invention relates to a high-power optical fibre laser comprising: an oscillator (1); a pumping laser (5) able to emit a high-power pumping optical radiation beam; and a signal-amplifying optical fibre (3) able to receive said optical source signal and said high-power pumping optical radiation beam so as to generate a high-power laser beam. According to the invention, said pumping laser comprises a plurality of pumping multimode laser diodes (7a-7f) and a laser cavity, said laser cavity comprising a double-clad fibre (4) comprising: a neodymium-doped monomode waveguide; a fibre Bragg grating (9) forming one end of said laser cavity; and a fibre reflector (11) forming the other end of said laser cavity, said monomode fibre laser being able to generate a laser radiation beam when it is optically pumped by a pumping radiation beam originating from the plurality of pumping laser diodes in order for said laser cavity to emit a high-power pumping laser radiation beam.</p>
