A novel nonlinear optical limiter (NOL) based on stimulated Brillouin scattering (SBS) in highly nonlinear fiber was proposed and experimentally demonstrated at 1550 nm wavelength. The nonlinear optical limiting effects of HNLF were characterized and demonstrated theoretically and experimentally. In a proof-of-concept experiment, we verified that the NOL based on a 50 m HNLF has excellent limiting performance due to its small effective area and high Brillouin gain coefficient. The linear transmittance and lowest nonlinear transmittance of the NOL were 87.5% and 11.9%, respectively.