The invention relates to a fiber laser device provided with automatic protection of semiconductor pumping sources, which is characterized by comprising a multimode pumping optical fiber combiner, a plurality of semiconductor pumping sources, a fiber laser device, a retroreflection laser power monitoring device and a driving power for semiconductor pumping sources. The multimode pumping optical fiber combiner is provided with N input multimode transmitting energy fibers and a pumping fiber, wherein, N is positive integer more than 1; the pumping fiber is connected with the input end of the fiber laser device; one of the N input multimode transmitting energy fibers is connected with the control end of the driving power of the semiconductor pumping sources by the retroreflection laser power monitoring device to judge whether the laser returned is too strong by monitoring the signal power of the returned laser of the idle pumping fiber and to automatically cut off the power supply of the semiconductor pumping sources according to the judgment so as to automatically protect the pumping source semiconductor laser. The fiber laser device of the invention has the advantages of simple structure, low cost and wide application.