In order to explore the possibility of using two-dimensional materials as saturable absorbers (SA) of passively Q-switched lasers, antimonene nanosheets were successfully prepared by pre-grinding liquid-phase-exfoliation (LPE) method. The phase composition, microstructure and absorption properties of the samples were characterized by Raman spectrometer, X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and UV-Vis-NIR spectrophotometer. Based on the prepared synthesized antimonene nanosheets SA, an all-solid-state passively Q-switched Nd∶GYAP laser at 1.3 μm was realized for the first time. The shortest pulse width is 589 ns, the repetition rate is 424 kHz, the peak power is 1.14 W, the average output power is 284 mW, and the maximum single pulse energy is 669.43 nJ. The results show that the antimonene nanosheets have the potential to become SA of all solid state Q-switched laser in the near infrared region.