The invention discloses an extra-bright single-mold fiber laser with a strong-coupled multi-mold rare-earth-doped ring core. The laser comprises a pumping source and an active fiber, wherein the active fiber includes a single-mold rare-earth-doped fiber core (4), a first silicon annular zone (61), a multi-mold rare-earth-doped ring core (2), a second silicon annular zone (62) and an outer coating layer (3) from inside to outside in sequence; the smallest distance between the surface of the single-mold rare-earth-doped fiber core and the internal surface of the multi-mold rare-earth-doped ring core is less than or equal to 5Mum and more than 1Mum; a first raster (51) and a second raster (52) are written in the two ends of the single-mold rare-earth-doped fiber core; or a high-reflecting film (8) corresponding to the laser light wavelength is plated at one end of the active fiber, and the second raster is written in the single-mold rare-earth-doped fiber core at the other end; or the high-reflecting film corresponding to the laser light wavelength is plated at one end of the active fiber, and the first raster and the second raster are written in the two ends of the single-mold rare-earth-doped fiber core. The laser has the strong coupling of the single-mold rare-earth-doped fiber core and the multi-mold rare-earth-doped ring core, thereby realizing high-power and extra-bright output of single-mold laser.