The invention discloses a narrow-linewidth frequency doubling vortex light laser, which comprises a pumping source, a pumping conversion device, a coupling lens group, a laser crystal, a temperature control device, a Brewster plate, a full-wave plate, a nonlinear optical crystal, a diaphragm and an output mirror which are sequentially arranged in the light propagation direction, wherein the pumping source outputs non-uniform pumping light after being coupled by the pumping conversion device and the coupling lens group; the left end face of the laser crystal and the output mirror form an optical resonant cavity, the Brewster plate is inserted into the cavity to polarize fundamental frequency vortex light, polarization selectivity loss is introduced by combining the full-wave plate and the nonlinear optical crystal to force the laser to operate in a single longitudinal mode, and the nonlinear optical crystal is used for frequency doubling of the vortex light in the cavity; and the outputmirror is slightly inclined. The narrow linewidth frequency doubling vortex light laser provided by the invention has the advantages of narrow linewidth, high mode purity, good light beam quality, simple structure, small size, convenience for system integration and the like.